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      <link:roleType id="OtherNetDetails" roleURI="http://www.aciworldwide.com/role/OtherNetDetails">
        <link:definition>9954730 - Disclosure - Other, Net (Details)</link:definition>
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      <link:roleType id="SegmentInformationSelectedFinancialDataDetails" roleURI="http://www.aciworldwide.com/role/SegmentInformationSelectedFinancialDataDetails">
        <link:definition>9954731 - Disclosure - Segment Information - Selected Financial Data (Details)</link:definition>
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        <link:definition>9954732 - Disclosure - Segment Information - Selected Financial Data, Revenues and Long lived Assets (Details)</link:definition>
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      <link:roleType id="IncomeTaxesAdditionalInformationDetails" roleURI="http://www.aciworldwide.com/role/IncomeTaxesAdditionalInformationDetails">
        <link:definition>9954733 - Disclosure - Income Taxes - Additional Information (Details)</link:definition>
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      <link:roleType id="CommitmentsandContingenciesDetails" roleURI="http://www.aciworldwide.com/role/CommitmentsandContingenciesDetails">
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  <xs:element id="aciw_USConsumerFinancialProtectionBureauAndStateAttorneysGeneralMember" abstract="true" name="USConsumerFinancialProtectionBureauAndStateAttorneysGeneralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="aciw_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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</xs:schema>
