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<!-- DFS ActiveDisclosure(SM) XBRL Schema Document - http://www.dfsco.com/financial-services/ -->
<!-- Creation Date      : 2019-03-01T17:04:50.6593970+00:00 -->
<!-- Version            : 3.3.6989.14284 -->
<!-- Package ID         : 5830569038f940f1b47371469582084e -->
<!-- Copyright (c) 2019 Donnelley Financial, LLC. All Rights Reserved. -->
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  <element id="achc_PioneerBehavioralHealthMember" name="PioneerBehavioralHealthMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_NumberOfFacilitiesOperatedByNonWhollyOwnedSubsidiaries" name="NumberOfFacilitiesOperatedByNonWhollyOwnedSubsidiaries" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <element id="achc_NonWhollyOwnedSubsidiariesMember" name="NonWhollyOwnedSubsidiariesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_CorporateReconcilingItemsAndEliminationsMember" name="CorporateReconcilingItemsAndEliminationsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_GoodwillIncreaseFromContributionOfRedeemableNoncontrollingInterests" name="GoodwillIncreaseFromContributionOfRedeemableNoncontrollingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <element id="achc_Plan401KMember" name="Plan401KMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_PartnershipInCareBenefitsPlanMember" name="PartnershipInCareBenefitsPlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_AnnuityContractsMember" name="AnnuityContractsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_OtherAssetMember" name="OtherAssetMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_ChangeInFairValueOfDerivativeInstrumentsMember" name="ChangeInFairValueOfDerivativeInstrumentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_QuarterlyFinancialInformationLineItems" name="QuarterlyFinancialInformationLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <element id="achc_QuarterlyFinancialInformationTable" name="QuarterlyFinancialInformationTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
</schema>


