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  <xs:element id="asgn_DebtCovenantMaximumSeniorSecuredDebtToEBITDARatioBeginningJune2027" abstract="false" name="DebtCovenantMaximumSeniorSecuredDebtToEBITDARatioBeginningJune2027" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="asgn_DebtCovenantMaximumSeniorSecuredDebtToEBITDARatioBeginningJune2028" abstract="false" name="DebtCovenantMaximumSeniorSecuredDebtToEBITDARatioBeginningJune2028" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="asgn_CalculationOfBasicAndDilutedEarningsPerShareAbstract" abstract="true" name="CalculationOfBasicAndDilutedEarningsPerShareAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="asgn_CorporateSGAExpenses" abstract="false" name="CorporateSGAExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="asgn_OtherFederalMember" abstract="true" name="OtherFederalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_NationalSecurityMember" abstract="true" name="NationalSecurityMember" 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_DepartmentOfDefenseIntelligenceAgenciesMember" abstract="true" name="DepartmentOfDefenseIntelligenceAgenciesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_RevenueTypeAxis" abstract="true" name="RevenueTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="asgn_RevenueTypeDomain" abstract="true" name="RevenueTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ConsumerAndIndustrialSectorMember" abstract="true" name="ConsumerAndIndustrialSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_TechnologyMediaAndTelecommunicationsSectorMember" abstract="true" name="TechnologyMediaAndTelecommunicationsSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="asgn_BusinessServicesSectorMember" abstract="true" name="BusinessServicesSectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
