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  <xs:element id="acm_TermLoanBFacilityMember" abstract="true" name="TermLoanBFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_DebtInstrumentTermExtension" abstract="false" name="DebtInstrumentTermExtension" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="acm_DebtInstrumentFloorRate" abstract="false" name="DebtInstrumentFloorRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="acm_SeniorNotes2027Member" abstract="true" name="SeniorNotes2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_DebtInstrumentRedemptionPeriodAfterFiveYearsMember" abstract="true" name="DebtInstrumentRedemptionPeriodAfterFiveYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_PaymentForDebtRedemptionMakeWholePortion" abstract="false" name="PaymentForDebtRedemptionMakeWholePortion" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_MaturityAxis" abstract="true" name="MaturityAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="acm_MaturityDomain" abstract="true" name="MaturityDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_February2023Member" abstract="true" name="February2023Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_FY2025FourthQuarterAcquisitionMember" abstract="true" name="FY2025FourthQuarterAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_CreditFacilityInvestmentMember" abstract="true" name="CreditFacilityInvestmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEarnedInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEarnedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="acm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEarnedInPeriodWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsEarnedInPeriodWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="acm_FinanceLeaseCostsAbstract" abstract="true" name="FinanceLeaseCostsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="acm_RightOfUseAssets" abstract="false" name="RightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_LeaseLiabilitiesCurrent" abstract="false" name="LeaseLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_LeaseLiabilitiesNoncurrent" abstract="false" name="LeaseLiabilitiesNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_WeightedAverageRemainingLeaseTermAbstract" abstract="true" name="WeightedAverageRemainingLeaseTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="acm_WeightedAverageDiscountRatesAbstract" abstract="true" name="WeightedAverageDiscountRatesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="acm_CashFlowLesseeAbstract" abstract="true" name="CashFlowLesseeAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="acm_LesseeOperatingLeaseLiabilityToBePaidDueAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidDueAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_FinanceLeaseLiabilityToBePaidDueAfterYearFour" abstract="false" name="FinanceLeaseLiabilityToBePaidDueAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_AccruedContractCostsCurrent" abstract="false" name="AccruedContractCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_OtherFinancialsInformationTable" abstract="true" name="OtherFinancialsInformationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="acm_OtherFinancialsInformationLineItems" abstract="true" name="OtherFinancialsInformationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="acm_AECOMCapitalSegmentMember" abstract="true" name="AECOMCapitalSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="acm_SubcontractorAndOtherDirectCosts" abstract="false" name="SubcontractorAndOtherDirectCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_EarningsBeforeInterestTaxDepreciationAndAmortization" abstract="false" name="EarningsBeforeInterestTaxDepreciationAndAmortization" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_GeneralAndAdministrativeExpenseAdjusted" abstract="false" name="GeneralAndAdministrativeExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="acm_IncomeLossAttributableToNonControllingInterestsContinuingOperations" abstract="false" name="IncomeLossAttributableToNonControllingInterestsContinuingOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
