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  <xs:element id="pega_CorporateIncentiveCompensationPlanMember" abstract="true" name="CorporateIncentiveCompensationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValueOfAwards" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValueOfAwards" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pega_ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationPercentageOfTargetIncentiveCompensationEligibleEmployeeElection" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCompensationPercentageOfTargetIncentiveCompensationEligibleEmployeeElection" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pega_EarningsPerShareTable" abstract="true" name="EarningsPerShareTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pega_EarningsPerShareLineItems" abstract="true" name="EarningsPerShareLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pega_DilutiveSecuritiesEffectOnEPSNumeratorConvertibleDebt" abstract="false" name="DilutiveSecuritiesEffectOnEPSNumeratorConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pega_TradeSecretMisappropriationMember" abstract="true" name="TradeSecretMisappropriationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_ViolationOfTheVirginiaComputerCrimesActMember" abstract="true" name="ViolationOfTheVirginiaComputerCrimesActMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_AppianCorpVPegasystemsIncYouyongZouMember" abstract="true" name="AppianCorpVPegasystemsIncYouyongZouMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_ClassActionCase12999AndCase11220Member" abstract="true" name="ClassActionCase12999AndCase11220Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_CaseNo.2584CV00541BLS1AndCaseNo.2584CV00539BLS1Member" abstract="true" name="CaseNo.2584CV00541BLS1AndCaseNo.2584CV00539BLS1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_PegasystemsV.AppianDefamationLitigationMember" abstract="true" name="PegasystemsV.AppianDefamationLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_SpecialDividendToShareholdersMember" abstract="true" name="SpecialDividendToShareholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_LostProfitsOfThirdPartyMember" abstract="true" name="LostProfitsOfThirdPartyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_DisgorgeOfCompanyProfitsMember" abstract="true" name="DisgorgeOfCompanyProfitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="pega_LegalFeesPostJudgementInterestRatePercentage" abstract="false" name="LegalFeesPostJudgementInterestRatePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pega_LettersOfCreditCanceledAmount" abstract="false" name="LettersOfCreditCanceledAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pega_PercentageOfSettlementClassThatOptedOutOfCourtApprovedSettlement" abstract="false" name="PercentageOfSettlementClassThatOptedOutOfCourtApprovedSettlement" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="pega_DianneLedinghamMember" abstract="true" name="DianneLedinghamMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
