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  <xs:element id="asgn_ECSMember" abstract="true" name="ECSMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_AssignmentMember" abstract="true" name="AssignmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_OperatingLeaseRightOfUseAssetsObtainedInExchangeForOperatingLeaseLiabilities" abstract="false" name="OperatingLeaseRightOfUseAssetsObtainedInExchangeForOperatingLeaseLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_ReconciliationOfNetIncomeToComprehensiveIncomeAbstract" abstract="true" name="ReconciliationOfNetIncomeToComprehensiveIncomeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_FederalTaxDeferredCaresAct" abstract="false" name="FederalTaxDeferredCaresAct" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_OxfordBusinessMember" abstract="true" name="OxfordBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_ProceedsFromSaleOfPropertyHeldForSaleNetTax" abstract="false" name="ProceedsFromSaleOfPropertyHeldForSaleNetTax" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_PermanentPlacementMember" abstract="true" name="PermanentPlacementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_CommercialBusinessMember" abstract="true" name="CommercialBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_ContractorRelationsMember" abstract="true" name="ContractorRelationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_FederalcivilianMember" abstract="true" name="FederalcivilianMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_LeapFrogMember" abstract="true" name="LeapFrogMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_A2021AcquisitionsMember" abstract="true" name="A2021AcquisitionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_NumberOfLeasedPropertiesOwnedByRelatedParties" abstract="false" name="NumberOfLeasedPropertiesOwnedByRelatedParties" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="asgn_ApexSegmentMember" abstract="true" name="ApexSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_A250MillionRevolvingCreditFacilityDueNovember2024Member" abstract="true" name="A250MillionRevolvingCreditFacilityDueNovember2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_AccountingStandardUpdateAbstract" abstract="true" name="AccountingStandardUpdateAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_DHAMember" abstract="true" name="DHAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_ScheduleOfAcquiredIntangibleAssetsByMajorClassTable" abstract="true" name="ScheduleOfAcquiredIntangibleAssetsByMajorClassTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="asgn_EarningsPerShareDilutedDiscontinuedOperations" abstract="false" name="EarningsPerShareDilutedDiscontinuedOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_IntangibleAssetsNetAbstract" abstract="true" name="IntangibleAssetsNetAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_AccumulatedAcquisitionSince2019Member" abstract="true" name="AccumulatedAcquisitionSince2019Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_NetIncomeFromDiscontinuedOperations" abstract="false" name="NetIncomeFromDiscontinuedOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_DisposalGroupLeaseLiabilityNoncurrent" abstract="false" name="DisposalGroupLeaseLiabilityNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_InterestRateTypeDomain" abstract="true" name="InterestRateTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_LongTermDebtCarryingValue" abstract="false" name="LongTermDebtCarryingValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_IntangibleAssetsLineItems" abstract="true" name="IntangibleAssetsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_RevenueTypeAxis" abstract="true" name="RevenueTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="asgn_IntersysMember" abstract="true" name="IntersysMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_FairValueLevel1Inputs" abstract="false" name="FairValueLevel1Inputs" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_CostplusfixedfeeContractMember" abstract="true" name="CostplusfixedfeeContractMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_CommercialBusinessAbstract" abstract="true" name="CommercialBusinessAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_RevenuebyCustomerTypeAbstract" abstract="true" name="RevenuebyCustomerTypeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_ScheduleOfAcquiredIntangibleAssetsByMajorClassTableTextBlock" abstract="false" name="ScheduleOfAcquiredIntangibleAssetsByMajorClassTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="asgn_PercentOfFederalTaxDeferredCaresAct" abstract="false" name="PercentOfFederalTaxDeferredCaresAct" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="asgn_DisposalGroupLeaseLiabilityCurrent" abstract="false" name="DisposalGroupLeaseLiabilityCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_CommercialandotherMember" abstract="true" name="CommercialandotherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_BankBaseRateMember" abstract="true" name="BankBaseRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
