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  <xs:element id="csgp_ContractwithCustomerLiabilityPriorPeriodAmountsRecognized" abstract="false" name="ContractwithCustomerLiabilityPriorPeriodAmountsRecognized" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_ContractwithCustomerLiabilityNewDeferralsNetofAmountsRecognizedinCurrentPeriod" abstract="false" name="ContractwithCustomerLiabilityNewDeferralsNetofAmountsRecognizedinCurrentPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_ScheduleOfInterestExpenseTableTextBlock" abstract="false" name="ScheduleOfInterestExpenseTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="csgp_LineOfCreditFacilityCovenantComplianceTotalLeverageRatio" abstract="false" name="LineOfCreditFacilityCovenantComplianceTotalLeverageRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="csgp_CommissionsIncurred" abstract="false" name="CommissionsIncurred" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_IncreaseInRevenue" abstract="false" name="IncreaseInRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_BusinessImmoMember" abstract="true" name="BusinessImmoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="csgp_LongTermDebtMaturityInterestPayments" abstract="false" name="LongTermDebtMaturityInterestPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_ProceedsFromSaleOfPropertyAndEquipmentAndOtherAssets" abstract="false" name="ProceedsFromSaleOfPropertyAndEquipmentAndOtherAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_A2800SeniorNotesMember" abstract="true" name="A2800SeniorNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="csgp_MultifamilyOnlineMarketplaceMember" abstract="true" name="MultifamilyOnlineMarketplaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="csgp_LongTermDebtMaturityInterestPaymentsAbstract" abstract="true" name="LongTermDebtMaturityInterestPaymentsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="csgp_AlternateBaseRateMember" abstract="true" name="AlternateBaseRateMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="csgp_AdjustmentsToAdditionalPaidInCapitalRestrictedStockSurrendered" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalRestrictedStockSurrendered" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_LongTermDebtMaturityInterestPaymentsAfterYearFour" abstract="false" name="LongTermDebtMaturityInterestPaymentsAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_NumberOfTradeReceivablesInMultifamilyPortfolio" abstract="false" name="NumberOfTradeReceivablesInMultifamilyPortfolio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="csgp_IndefiniteLivedIntangibleAssetsWrittenOff" abstract="false" name="IndefiniteLivedIntangibleAssetsWrittenOff" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_PerformanceBasedRestrictedStockMember" abstract="true" name="PerformanceBasedRestrictedStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="csgp_ChangeinContractwithCustomerLiabilityRollForward" abstract="true" name="ChangeinContractwithCustomerLiabilityRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="csgp_LongTermDebtMaturityInterestPaymentsYearFour" abstract="false" name="LongTermDebtMaturityInterestPaymentsYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_ProceedsFromExerciseOfStockOptionsAndEspp" abstract="false" name="ProceedsFromExerciseOfStockOptionsAndEspp" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="csgp_DeferredSalesCommissionAmortizationPeriod" abstract="false" name="DeferredSalesCommissionAmortizationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="csgp_SupplementalBalanceSheetInformationRelatedtoLeasesTableTextBlock" abstract="false" name="SupplementalBalanceSheetInformationRelatedtoLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="csgp_HomesnapMember" abstract="true" name="HomesnapMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
