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  <xsd:element abstract="true" id="csgp_OptionsOutstanding7Member" name="OptionsOutstanding7Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="csgp_OptionsOutstanding8Member" name="OptionsOutstanding8Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="csgp_OptionsOutstanding9Member" name="OptionsOutstanding9Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_PercentageOfCompanyMatchOfEmployeeContribution" name="PercentageOfCompanyMatchOfEmployeeContribution" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_PercentageOfLoanAmortizationInYearFive" name="PercentageOfLoanAmortizationInYearFive" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_PercentageOfLoanAmortizationInYearFour" name="PercentageOfLoanAmortizationInYearFour" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_PercentageOfLoanAmortizationInYearOne" name="PercentageOfLoanAmortizationInYearOne" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_PercentageOfLoanAmortizationInYearThree" name="PercentageOfLoanAmortizationInYearThree" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_PercentageOfLoanAmortizationInYearTwo" name="PercentageOfLoanAmortizationInYearTwo" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_PercentageOfPurchasePriceOfCompanysCommonStockToMarketPrice" name="PercentageOfPurchasePriceOfCompanysCommonStockToMarketPrice" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="csgp_PerformancebasedRSAswithMarketConditionMember" name="PerformancebasedRSAswithMarketConditionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_ProceedsFromExerciseOfStockOptionsAndEspp" name="ProceedsFromExerciseOfStockOptionsAndEspp" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="csgp_RealizedTaxBenefitsRelatedToOperatingLossCarryforward" name="RealizedTaxBenefitsRelatedToOperatingLossCarryforward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="csgp_SharebasedCompensationSharesCanceledorExpiredUnderStockOptionPlansExercisePriceRange" name="SharebasedCompensationSharesCanceledorExpiredUnderStockOptionPlansExercisePriceRange" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_SharebasedCompensationSharesExercisedUnderStockOptionPlansExercisePriceRange" name="SharebasedCompensationSharesExercisedUnderStockOptionPlansExercisePriceRange" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_SharebasedCompensationSharesGrantedUnderStockOptionPlansExercisePriceRange" name="SharebasedCompensationSharesGrantedUnderStockOptionPlansExercisePriceRange" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange" name="SharebasedCompensationSharesOutstandingUnderStockOptionPlansExercisePriceRange" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_SharesAvailableEmployeeStockPurchasePlan" name="SharesAvailableEmployeeStockPurchasePlan" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="csgp_SubscriptionBasedLicensingAgreementMinimumTermYears" name="SubscriptionBasedLicensingAgreementMinimumTermYears" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="csgp_SwinglineLoanMember" name="SwinglineLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="csgp_ThomasDailyMember" name="ThomasDailyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="csgp_UnrecognizedTaxBenefitsReversalOfInterestandPenalties" name="UnrecognizedTaxBenefitsReversalOfInterestandPenalties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
</xsd:schema>
