SEC Info - Vse Corp - ‘10-Q’ for 3/31/15

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Vse Corp – ‘10-Q’ for 3/31/15 – ‘EX-101.DEF’

On: Friday, 5/1/15, at 4:39pm ET · For: 3/31/15 · Accession #: 102752-15-33 · File #: 0-03676

  As Of               Filer                 Filing    For·On·As Docs:Size

 5/01/15  Vse Corp                          10-Q        3/31/15   44:4M

Quarterly Report — Form 10-Q — Sect. 13 / 15(d) – SEA’34
Filing Table of Contents

Document/Exhibit                   Description                      Pages   Size 

 1: 10-Q        Vse Corporation Form 10-Q March 31, 2015            HTML    296K 
 2: EX-31.1     Section 302 CEO Certification                       HTML     19K 
 3: EX-31.2     Section 302 CFO and Pao Certification               HTML     19K 
 4: EX-32.1     Section 906 CEO Certification                       HTML     15K 
 5: EX-32.2     Section 906 CFO and Pao Certification               HTML     15K 
26: R1          Document and Entity Information                     HTML     40K 
19: R2          Unaudited Consolidated Balance Sheets               HTML    122K 
24: R3          Unaudited Consolidated Balance Sheets               HTML     27K 
                (Parenthetical)                                                  
28: R4          Unaudited Consolidated Statements of Income         HTML    100K 
40: R5          Unaudited Consolidated Statements of Comprehensive  HTML     28K 
                Income                                                           
20: R6          Unaudited Consolidated Statements of Cash Flows     HTML    101K 
23: R7          Basis of Presentation                               HTML     19K 
18: R8          Acquisition                                         HTML     47K 
14: R9          Debt                                                HTML     23K 
41: R10         Earnings Per Share                                  HTML     24K 
30: R11         Commitments and Contingencies                       HTML     23K 
29: R12         Business Segments and Customer Information          HTML     88K 
35: R13         Goodwill and Intangible Assets                      HTML     53K 
36: R14         Fair Value Measurements                             HTML     41K 
34: R15         Recently Issued Accounting Pronouncements           HTML     18K 
37: R16         Acquisition (Tables)                                HTML     39K 
25: R17         Earnings Per Share (Tables)                         HTML     23K 
27: R18         Business Segments and Customer Information          HTML     84K 
                (Tables)                                                         
33: R19         Goodwill and Intangible Assets (Tables)             HTML     55K 
44: R20         Fair Value Measurements (Tables)                    HTML     40K 
38: R21         Acquisition (Details)                               HTML    107K 
21: R22         Debt (Details)                                      HTML     90K 
31: R23         Earnings Per Share (Details)                        HTML     24K 
22: R24         Commitments and Contingencies - (Details)           HTML     29K 
13: R25         Business Segments and Customer Information          HTML     53K 
                (Details)                                                        
39: R26         Business Segments and Customer Information, Major   HTML     58K 
                Customers (Details)                                              
42: R27         Goodwill and Intangible Assets (Details)            HTML     74K 
17: R28         Fair Value Measurements (Details)                   HTML     59K 
16: R29         Fair Value Measurements, Unobservable Input         HTML     33K 
                Reconciliation (Details)                                         
43: XML         IDEA XML File -- Filing Summary                      XML     60K 
12: EXCEL       IDEA Workbook of Financial Reports                  XLSX     77K 
15: EXCEL       IDEA Workbook of Financial Reports (.xls)            XLS    487K 
 6: EX-101.INS  XBRL Instance -- vsec-20150331                       XML    798K 
 8: EX-101.CAL  XBRL Calculations -- vsec-20150331_cal               XML    121K 
 9: EX-101.DEF  XBRL Definitions -- vsec-20150331_def                XML    282K 
10: EX-101.LAB  XBRL Labels -- vsec-20150331_lab                     XML    922K 
11: EX-101.PRE  XBRL Presentations -- vsec-20150331_pre              XML    511K 
 7: EX-101.SCH  XBRL Schema -- vsec-20150331                         XSD     89K 
32: ZIP         XBRL Zipped Folder -- 0000102752-15-000033-xbrl      Zip     88K

‘EX-101.DEF’ — XBRL Definitions — vsec-20150331_def

This Exhibit is an XBRL XML File.

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<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:t1="http://xbrl.org/2005/xbrldt">

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<link:roleRef roleURI="http://vsecorp.com/role/DebtDetails" xlink:type="simple" xlink:href="vsec-20150331.xsd#DebtDetails"/>

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<link:roleRef roleURI="http://vsecorp.com/role/AcquisitionDetails" xlink:type="simple" xlink:href="vsec-20150331.xsd#AcquisitionDetails"/>

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<link:roleRef roleURI="http://vsecorp.com/role/GoodwillAndIntangibleAssetsTables" xlink:type="simple" xlink:href="vsec-20150331.xsd#GoodwillAndIntangibleAssetsTables"/>

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<link:roleRef roleURI="http://vsecorp.com/role/AcquisitionTables" xlink:type="simple" xlink:href="vsec-20150331.xsd#AcquisitionTables"/>

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<link:roleRef roleURI="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfCashFlows" xlink:type="simple" xlink:href="vsec-20150331.xsd#UnauditedConsolidatedStatementsOfCashFlows"/>

<link:roleRef roleURI="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfComprehensiveIncome" xlink:type="simple" xlink:href="vsec-20150331.xsd#UnauditedConsolidatedStatementsOfComprehensiveIncome"/>

<link:roleRef roleURI="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfIncome" xlink:type="simple" xlink:href="vsec-20150331.xsd#UnauditedConsolidatedStatementsOfIncome"/>

<link:roleRef roleURI="http://vsecorp.com/role/UnauditedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" xlink:href="vsec-20150331.xsd#UnauditedConsolidatedBalanceSheetsParenthetical"/>

<link:roleRef roleURI="http://vsecorp.com/role/UnauditedConsolidatedBalanceSheets" xlink:type="simple" xlink:href="vsec-20150331.xsd#UnauditedConsolidatedBalanceSheets"/>

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<link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>

<link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>

<link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>

<link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>

<link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/DocumentAndEntityInformation"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/UnauditedConsolidatedBalanceSheets"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/UnauditedConsolidatedBalanceSheetsParenthetical"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfIncome"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfComprehensiveIncome"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/UnauditedConsolidatedStatementsOfCashFlows"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/BasisOfPresentation"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/Acquisition"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/Debt"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/EarningsPerShare"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/CommitmentsAndContingencies"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/BusinessSegmentsAndCustomerInformation"/>

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<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/RecentlyIssuedAccountingPronouncements"/>

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<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/EarningsPerShareTables"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_BusinessAcquisitionNumberOfBusinessesAcquired" xlink:label="BusinessAcquisitionNumberOfBusinessesAcquired" xlink:title="BusinessAcquisitionNumberOfBusinessesAcquired"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessAcquisitionNumberOfBusinessesAcquired" xlink:title="definition: BusinessAcquisitionLineItems to BusinessAcquisitionNumberOfBusinessesAcquired" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_MaximumPotentialCashPayment" xlink:label="MaximumPotentialCashPayment" xlink:title="MaximumPotentialCashPayment"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="MaximumPotentialCashPayment" xlink:title="definition: BusinessAcquisitionLineItems to MaximumPotentialCashPayment" order="2.0"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_vse_BusinessAcquisitionEstimatedCashAndWorkingCapitalAdjustment" xlink:label="vse_BusinessAcquisitionEstimatedCashAndWorkingCapitalAdjustment" xlink:title="vse_BusinessAcquisitionEstimatedCashAndWorkingCapitalAdjustment"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_BusinessAcquisitionEstimatedWorkingCapitalAdjustment" xlink:label="BusinessAcquisitionEstimatedWorkingCapitalAdjustment" xlink:title="BusinessAcquisitionEstimatedWorkingCapitalAdjustment"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="FiniteLivedIntangibleAssetUsefulLife" xlink:title="FiniteLivedIntangibleAssetUsefulLife"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" order="20.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" order="21.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" order="22.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_Goodwill" xlink:label="Goodwill" xlink:title="Goodwill"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" order="24.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_vse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherCurrentLiabilities" xlink:label="vse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherCurrentLiabilities" xlink:title="vse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherCurrentLiabilities"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="vse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherCurrentLiabilities" xlink:title="definition: BusinessAcquisitionLineItems to vse_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedExpensesAndOtherCurrentLiabilities" order="25.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilitiesNoncurrent" order="26.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_vse_BusinessAcquisitionCostOfAcquiredEntityInitialPurchasePrice" xlink:label="vse_BusinessAcquisitionCostOfAcquiredEntityInitialPurchasePrice" xlink:title="vse_BusinessAcquisitionCostOfAcquiredEntityInitialPurchasePrice"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="vse_BusinessAcquisitionCostOfAcquiredEntityInitialPurchasePrice" xlink:title="definition: BusinessAcquisitionLineItems to vse_BusinessAcquisitionCostOfAcquiredEntityInitialPurchasePrice" order="27.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:label="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" order="28.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:title="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionLineItems" xlink:to="BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:title="definition: BusinessAcquisitionLineItems to BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" order="29.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="BusinessAcquisitionLineItems" xlink:to="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:title="definition: BusinessAcquisitionLineItems to ScheduleOfBusinessAcquisitionsByAcquisitionTable" order="30.0" t1:closed="true" t1:contextElement="segment"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="BusinessAcquisitionAxis" xlink:title="BusinessAcquisitionAxis"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="BusinessAcquisitionAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to BusinessAcquisitionAxis" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain" xlink:title="BusinessAcquisitionAcquireeDomain"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="BusinessAcquisitionAcquireeDomain_2" xlink:title="BusinessAcquisitionAcquireeDomain"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="BusinessAcquisitionAxis" xlink:to="BusinessAcquisitionAcquireeDomain_2" xlink:title="definition: BusinessAcquisitionAxis to BusinessAcquisitionAcquireeDomain_2" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AviationAcquisitionsMember" xlink:label="AviationAcquisitionsMember" xlink:title="AviationAcquisitionsMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="BusinessAcquisitionAcquireeDomain" xlink:to="AviationAcquisitionsMember" xlink:title="definition: BusinessAcquisitionAcquireeDomain to AviationAcquisitionsMember" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="FiniteLivedIntangibleAssetsByMajorClassAxis"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfBusinessAcquisitionsByAcquisitionTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="definition: FiniteLivedIntangibleAssetsByMajorClassAxis to FiniteLivedIntangibleAssetsMajorClassNameDomain_2" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="CustomerRelationshipsMember" xlink:title="CustomerRelationshipsMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="CustomerRelationshipsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to CustomerRelationshipsMember" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TrademarksAndTradeNamesMember" xlink:label="TrademarksAndTradeNamesMember" xlink:title="TrademarksAndTradeNamesMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TrademarksAndTradeNamesMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TrademarksAndTradeNamesMember" order="2.0"/>

</link:definitionLink>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/AcquisitionDetailsCalc2"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/DebtDetails">

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="DebtInstrumentLineItems" xlink:title="DebtInstrumentLineItems"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="DebtInstrumentMaturityDate" xlink:title="DebtInstrumentMaturityDate"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentMaturityDate" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentMaturityDate" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="UnamortizedDebtIssuanceExpense" xlink:title="UnamortizedDebtIssuanceExpense"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="UnamortizedDebtIssuanceExpense" xlink:title="definition: DebtInstrumentLineItems to UnamortizedDebtIssuanceExpense" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AmortizationPeriodOfDebtIssuanceCosts" xlink:label="AmortizationPeriodOfDebtIssuanceCosts" xlink:title="AmortizationPeriodOfDebtIssuanceCosts"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="AmortizationPeriodOfDebtIssuanceCosts" xlink:title="definition: DebtInstrumentLineItems to AmortizationPeriodOfDebtIssuanceCosts" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebtByMaturityAbstract" xlink:label="LongTermDebtByMaturityAbstract" xlink:title="LongTermDebtByMaturityAbstract"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtByMaturityAbstract" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtByMaturityAbstract" order="4.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="DebtInstrumentCarryingAmount" xlink:title="DebtInstrumentCarryingAmount"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentCarryingAmount" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentCarryingAmount" order="5.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="LineOfCreditFacilityMaximumBorrowingCapacity"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityMaximumBorrowingCapacity" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityMaximumBorrowingCapacity" order="6.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_RevolvingLoansPotentialIncrementInMaximumBorrowingCapacity" xlink:label="RevolvingLoansPotentialIncrementInMaximumBorrowingCapacity" xlink:title="RevolvingLoansPotentialIncrementInMaximumBorrowingCapacity"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="RevolvingLoansPotentialIncrementInMaximumBorrowingCapacity" xlink:title="definition: DebtInstrumentLineItems to RevolvingLoansPotentialIncrementInMaximumBorrowingCapacity" order="7.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LineOfCreditFacilityAmountOutstanding" xlink:label="LineOfCreditFacilityAmountOutstanding" xlink:title="LineOfCreditFacilityAmountOutstanding"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LineOfCreditFacilityAmountOutstanding" xlink:title="definition: DebtInstrumentLineItems to LineOfCreditFacilityAmountOutstanding" order="8.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LettersOfCreditOutstandingAmount" xlink:label="LettersOfCreditOutstandingAmount" xlink:title="LettersOfCreditOutstandingAmount"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LettersOfCreditOutstandingAmount" xlink:title="definition: DebtInstrumentLineItems to LettersOfCreditOutstandingAmount" order="9.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LongTermDebt" xlink:label="LongTermDebt" xlink:title="LongTermDebt"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebt" xlink:title="definition: DebtInstrumentLineItems to LongTermDebt" order="10.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="DebtInstrumentBasisSpreadOnVariableRate1"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentBasisSpreadOnVariableRate1" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentBasisSpreadOnVariableRate1" order="11.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1" xlink:label="MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1" xlink:title="MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1" xlink:title="definition: DebtInstrumentLineItems to MaximumLengthOfTimeHedgedInInterestRateCashFlowHedge1" order="12.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_DerivativeNotionalAmount" xlink:label="DerivativeNotionalAmount" xlink:title="DerivativeNotionalAmount"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DerivativeNotionalAmount" xlink:title="definition: DebtInstrumentLineItems to DerivativeNotionalAmount" order="13.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum" xlink:label="DebtInstrumentInterestRateStatedPercentageRateRangeMinimum" xlink:title="DebtInstrumentInterestRateStatedPercentageRateRangeMinimum"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentInterestRateStatedPercentageRateRangeMinimum" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentInterestRateStatedPercentageRateRangeMinimum" order="14.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum" xlink:label="DebtInstrumentInterestRateStatedPercentageRateRangeMaximum" xlink:title="DebtInstrumentInterestRateStatedPercentageRateRangeMaximum"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentInterestRateStatedPercentageRateRangeMaximum" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentInterestRateStatedPercentageRateRangeMaximum" order="15.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="DebtInstrumentInterestRateEffectivePercentage" xlink:title="DebtInstrumentInterestRateEffectivePercentage"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="DebtInstrumentInterestRateEffectivePercentage" xlink:title="definition: DebtInstrumentLineItems to DebtInstrumentInterestRateEffectivePercentage" order="16.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_InterestExpense" xlink:label="InterestExpense" xlink:title="InterestExpense"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="InterestExpense" xlink:title="definition: DebtInstrumentLineItems to InterestExpense" order="17.0"/>

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<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="DebtInstrumentLineItems" xlink:to="LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" xlink:title="definition: DebtInstrumentLineItems to LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" order="18.0"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_TermLoanFacilityMember" xlink:label="TermLoanFacilityMember" xlink:title="TermLoanFacilityMember"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="LondonInterbankOfferedRateLIBORMember" xlink:title="LondonInterbankOfferedRateLIBORMember"/>

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<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/CommitmentsAndContingenciesDetails"/>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/BusinessSegmentsAndCustomerInformationDetails">

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_SupplyChainManagementGroupMember" xlink:label="SupplyChainManagementGroupMember" xlink:title="SupplyChainManagementGroupMember"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AviationAcquisitionsMember" xlink:label="AviationAcquisitionsMember" xlink:title="AviationAcquisitionsMember"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_FederalGroupMember" xlink:label="FederalGroupMember" xlink:title="FederalGroupMember"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_ItEnergyAndManagementConsultingGroupMember" xlink:label="ItEnergyAndManagementConsultingGroupMember" xlink:title="ItEnergyAndManagementConsultingGroupMember"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_InfrastructureGroupMember" xlink:label="InfrastructureGroupMember" xlink:title="InfrastructureGroupMember"/>

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<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_CorporateUnallocatedMember" xlink:label="CorporateUnallocatedMember" xlink:title="CorporateUnallocatedMember"/>

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</link:definitionLink>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/BusinessSegmentsAndCustomerInformationMajorCustomersDetails">

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_MajorCustomersAxis" xlink:label="MajorCustomersAxis" xlink:title="MajorCustomersAxis"/>

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<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="ConcentrationRiskTypeDomain" xlink:title="ConcentrationRiskTypeDomain"/>

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<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="MajorCustomersAxis" xlink:to="ConcentrationRiskTypeDomain_2" xlink:title="definition: MajorCustomersAxis to ConcentrationRiskTypeDomain_2" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_USNavyMember" xlink:label="USNavyMember" xlink:title="USNavyMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="USNavyMember" xlink:title="definition: ConcentrationRiskTypeDomain to USNavyMember" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_USArmyArmyReserveMember" xlink:label="USArmyArmyReserveMember" xlink:title="USArmyArmyReserveMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="USArmyArmyReserveMember" xlink:title="definition: ConcentrationRiskTypeDomain to USArmyArmyReserveMember" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_USAirForceMember" xlink:label="USAirForceMember" xlink:title="USAirForceMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="USAirForceMember" xlink:title="definition: ConcentrationRiskTypeDomain to USAirForceMember" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_TotalDepartmentOfDefenseMember" xlink:label="TotalDepartmentOfDefenseMember" xlink:title="TotalDepartmentOfDefenseMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="TotalDepartmentOfDefenseMember" xlink:title="definition: ConcentrationRiskTypeDomain to TotalDepartmentOfDefenseMember" order="4.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_UsPostalServiceMember" xlink:label="UsPostalServiceMember" xlink:title="UsPostalServiceMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="UsPostalServiceMember" xlink:title="definition: ConcentrationRiskTypeDomain to UsPostalServiceMember" order="5.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_DepartmentOfEnergyMember" xlink:label="DepartmentOfEnergyMember" xlink:title="DepartmentOfEnergyMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="DepartmentOfEnergyMember" xlink:title="definition: ConcentrationRiskTypeDomain to DepartmentOfEnergyMember" order="6.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_DepartmentOfTreasuryMember" xlink:label="DepartmentOfTreasuryMember" xlink:title="DepartmentOfTreasuryMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="DepartmentOfTreasuryMember" xlink:title="definition: ConcentrationRiskTypeDomain to DepartmentOfTreasuryMember" order="7.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_GovernmentMember" xlink:label="GovernmentMember" xlink:title="GovernmentMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="GovernmentMember" xlink:title="definition: ConcentrationRiskTypeDomain to GovernmentMember" order="8.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_TotalFederalCivilAgenciesMember" xlink:label="TotalFederalCivilAgenciesMember" xlink:title="TotalFederalCivilAgenciesMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="TotalFederalCivilAgenciesMember" xlink:title="definition: ConcentrationRiskTypeDomain to TotalFederalCivilAgenciesMember" order="9.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_CommercialMember" xlink:label="CommercialMember" xlink:title="CommercialMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ConcentrationRiskTypeDomain" xlink:to="CommercialMember" xlink:title="definition: ConcentrationRiskTypeDomain to CommercialMember" order="10.0"/>

</link:definitionLink>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/GoodwillAndIntangibleAssetsDetails">

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="FiniteLivedIntangibleAssetsLineItems" xlink:title="FiniteLivedIntangibleAssetsLineItems"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ImpairmentOfIntangibleAssetsFinitelived" xlink:label="ImpairmentOfIntangibleAssetsFinitelived" xlink:title="ImpairmentOfIntangibleAssetsFinitelived"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="ImpairmentOfIntangibleAssetsFinitelived" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to ImpairmentOfIntangibleAssetsFinitelived" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedContractualRightsGross" xlink:label="FiniteLivedContractualRightsGross" xlink:title="FiniteLivedContractualRightsGross"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedContractualRightsGross" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedContractualRightsGross" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AcquiredTechnologies" xlink:label="AcquiredTechnologies" xlink:title="AcquiredTechnologies"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="AcquiredTechnologies" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to AcquiredTechnologies" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedTradeNamesGross" xlink:label="FiniteLivedTradeNamesGross" xlink:title="FiniteLivedTradeNamesGross"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedTradeNamesGross" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedTradeNamesGross" order="4.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNetAbstract" xlink:label="FiniteLivedIntangibleAssetsNetAbstract" xlink:title="FiniteLivedIntangibleAssetsNetAbstract"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsNetAbstract" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsNetAbstract" order="5.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="FiniteLivedIntangibleAssetsGross" xlink:title="FiniteLivedIntangibleAssetsGross"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsGross" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsGross" order="6.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="FiniteLivedIntangibleAssetsAccumulatedAmortization"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsAccumulatedAmortization" order="7.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AccumulatedImpairmentLoss" xlink:label="AccumulatedImpairmentLoss" xlink:title="AccumulatedImpairmentLoss"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="AccumulatedImpairmentLoss" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to AccumulatedImpairmentLoss" order="8.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="FiniteLivedIntangibleAssetsNet" xlink:title="FiniteLivedIntangibleAssetsNet"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="FiniteLivedIntangibleAssetsNet" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to FiniteLivedIntangibleAssetsNet" order="9.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="ScheduleOfFiniteLivedIntangibleAssetsTable"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FiniteLivedIntangibleAssetsLineItems" xlink:to="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:title="definition: FiniteLivedIntangibleAssetsLineItems to ScheduleOfFiniteLivedIntangibleAssetsTable" order="10.0" t1:closed="true" t1:contextElement="segment"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:title="definition: ScheduleOfFiniteLivedIntangibleAssetsTable to FiniteLivedIntangibleAssetsByMajorClassAxis" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="FiniteLivedIntangibleAssetsMajorClassNameDomain_2" xlink:title="FiniteLivedIntangibleAssetsMajorClassNameDomain"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ContractualRightsMember" xlink:label="ContractualRightsMember" xlink:title="ContractualRightsMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="ContractualRightsMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to ContractualRightsMember" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_PatentedTechnologyMember" xlink:label="PatentedTechnologyMember" xlink:title="PatentedTechnologyMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="PatentedTechnologyMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to PatentedTechnologyMember" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_TradeNamesMember" xlink:label="TradeNamesMember" xlink:title="TradeNamesMember"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="TradeNamesMember" xlink:title="definition: FiniteLivedIntangibleAssetsMajorClassNameDomain to TradeNamesMember" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_GoodwillLineItems" xlink:label="GoodwillLineItems" xlink:title="GoodwillLineItems"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_GoodwillRollForward" xlink:label="GoodwillRollForward" xlink:title="GoodwillRollForward"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="GoodwillLineItems" xlink:to="GoodwillRollForward" xlink:title="definition: GoodwillLineItems to GoodwillRollForward" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_Goodwill" xlink:label="Goodwill" xlink:title="Goodwill"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="GoodwillLineItems" xlink:to="Goodwill" xlink:title="definition: GoodwillLineItems to Goodwill" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_GoodwillAcquiredDuringPeriod" xlink:label="GoodwillAcquiredDuringPeriod" xlink:title="GoodwillAcquiredDuringPeriod"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="GoodwillLineItems" xlink:to="GoodwillAcquiredDuringPeriod" xlink:title="definition: GoodwillLineItems to GoodwillAcquiredDuringPeriod" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="ScheduleOfGoodwillTable" xlink:title="ScheduleOfGoodwillTable"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="GoodwillLineItems" xlink:to="ScheduleOfGoodwillTable" xlink:title="definition: GoodwillLineItems to ScheduleOfGoodwillTable" order="4.0" t1:closed="true" t1:contextElement="segment"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="ScheduleOfGoodwillTable" xlink:to="StatementBusinessSegmentsAxis" xlink:title="definition: ScheduleOfGoodwillTable to StatementBusinessSegmentsAxis" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SegmentDomain" xlink:label="SegmentDomain" xlink:title="SegmentDomain"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_SegmentDomain" xlink:label="SegmentDomain_2" xlink:title="SegmentDomain"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_AviationAcquisitionsMember" xlink:label="AviationAcquisitionsMember" xlink:title="AviationAcquisitionsMember"/>

</link:definitionLink>

<link:definitionLink xlink:type="extended" xlink:role="http://vsecorp.com/role/FairValueMeasurementsDetails">

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:title="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_MutualFundsHeldInDscPlanFairValueDisclosure" xlink:label="MutualFundsHeldInDscPlanFairValueDisclosure" xlink:title="MutualFundsHeldInDscPlanFairValueDisclosure"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="MutualFundsHeldInDscPlanFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to MutualFundsHeldInDscPlanFairValueDisclosure" order="1.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_InterestRateSwaps" xlink:label="InterestRateSwaps" xlink:title="InterestRateSwaps"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="InterestRateSwaps" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to InterestRateSwaps" order="2.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_CurrentPortionOfEarnOutObligationFairValueDisclosure" xlink:label="CurrentPortionOfEarnOutObligationFairValueDisclosure" xlink:title="CurrentPortionOfEarnOutObligationFairValueDisclosure"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="CurrentPortionOfEarnOutObligationFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to CurrentPortionOfEarnOutObligationFairValueDisclosure" order="3.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_EarnOutObligationsFairValueDisclosure" xlink:label="EarnOutObligationsFairValueDisclosure" xlink:title="EarnOutObligationsFairValueDisclosure"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="EarnOutObligationsFairValueDisclosure" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to EarnOutObligationsFairValueDisclosure" order="4.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_IncomeTaxExpenseBenefitOnInterestRateSwap" xlink:label="IncomeTaxExpenseBenefitOnInterestRateSwap" xlink:title="IncomeTaxExpenseBenefitOnInterestRateSwap"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="IncomeTaxExpenseBenefitOnInterestRateSwap" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to IncomeTaxExpenseBenefitOnInterestRateSwap" order="5.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_MaximumPotentialCashPayment" xlink:label="MaximumPotentialCashPayment" xlink:title="MaximumPotentialCashPayment"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="MaximumPotentialCashPayment" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to MaximumPotentialCashPayment" order="6.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_BusinessCombinationMaximumPotentialEarnOutPaymentsPostAcquisitionPeriod" xlink:label="BusinessCombinationMaximumPotentialEarnOutPaymentsPostAcquisitionPeriod" xlink:title="BusinessCombinationMaximumPotentialEarnOutPaymentsPostAcquisitionPeriod"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="BusinessCombinationMaximumPotentialEarnOutPaymentsPostAcquisitionPeriod" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to BusinessCombinationMaximumPotentialEarnOutPaymentsPostAcquisitionPeriod" order="7.0"/>

<link:loc xlink:type="locator" xlink:href="vsec-20150331.xsd#vsec_PaymentOfEarnOutObligation" xlink:label="PaymentOfEarnOutObligation" xlink:title="PaymentOfEarnOutObligation"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="PaymentOfEarnOutObligation" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to PaymentOfEarnOutObligation" order="8.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueInputsDiscountRate" xlink:label="FairValueInputsDiscountRate" xlink:title="FairValueInputsDiscountRate"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="FairValueInputsDiscountRate" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to FairValueInputsDiscountRate" order="9.0"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:title="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>

<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:title="definition: FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems to FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" order="10.0" t1:closed="true" t1:contextElement="segment"/>

<link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2013/elts/us-gaap-2013-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="FairValueByMeasurementFrequencyAxis" xlink:title="FairValueByMeasurementFrequencyAxis"/>

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Filing Submission 0000102752-15-000033 – Alternative Formats (Word / Rich Text, HTML, Plain Text, et al.)

Vse Corp – ‘10-Q’ for 3/31/15 – ‘EX-101.DEF’

On: Friday, 5/1/15, at 4:39pm ET · For: 3/31/15 · Accession #: 102752-15-33 · File #: 0-03676

Previous ‘10-Q’: ‘10-Q’ on 10/30/14 for 9/30/14 · Next: ‘10-Q’ on 7/30/15 for 6/30/15 · Latest: ‘10-Q’ on 11/2/23 for 9/30/23

Quarterly Report — Form 10-Q — Sect. 13 / 15(d) – SEA’34Filing Table of Contents

‘EX-101.DEF’ — XBRL Definitions — vsec-20150331_def

This Exhibit is an XBRL XML File.

Quarterly Report — Form 10-Q — Sect. 13 / 15(d) – SEA’34
Filing Table of Contents