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  <xsd:element abstract="true" id="cdw_A2013LongTermIncentivePlanMember" name="A2013LongTermIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_AbrMember" name="AbrMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_AccountsPayableInventoryFinancing" name="AccountsPayableInventoryFinancing" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_AccountsPayableInventoryFinancingCollateralizedMember" name="AccountsPayableInventoryFinancingCollateralizedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_AccountsPayableInventoryFinancingMember" name="AccountsPayableInventoryFinancingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_AdvancesToFromAffiliates" name="AdvancesToFromAffiliates" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_AmountOwedUnderRevolvingLoanFinancingAgreement" name="AmountOwedUnderRevolvingLoanFinancingAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_CDWUKMember" name="CDWUKMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CDWUKRevolvingCreditFacilityMember" name="CDWUKRevolvingCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CDWUKTermLoanMember" name="CDWUKTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_Capagreementeffective1117123118Member" name="Capagreementeffective1117123118Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_CashAvailabilityPercentageofBorrowingBase" name="CashAvailabilityPercentageofBorrowingBase" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_ClassBCommonUnitMember" name="ClassBCommonUnitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CoIssuerMember" name="CoIssuerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_ComputerSoftwareMember" name="ComputerSoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CoworkerRetirementandOtherCompensationBenefitsLineItems" name="CoworkerRetirementandOtherCompensationBenefitsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CoworkerRetirementandOtherCompensationBenefitsTable" name="CoworkerRetirementandOtherCompensationBenefitsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CoworkerStockPurchasePlanMember" name="CoworkerStockPurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_CustomerRelationshipsandContractsMember" name="CustomerRelationshipsandContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_DebtInstrumentUnusedBorrowingCapacityFeeinbps" name="DebtInstrumentUnusedBorrowingCapacityFeeinbps" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_DeferredFinanceCostsNetandUnamortizedPremium" name="DeferredFinanceCostsNetandUnamortizedPremium" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_DeferredIncomeTaxExpenseRelatedtoBasisDifferenceinForeignInvestment" name="DeferredIncomeTaxExpenseRelatedtoBasisDifferenceinForeignInvestment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_DeferredTaxAssetsDeferredInterest" name="DeferredTaxAssetsDeferredInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_DeferredTaxAssetsRent" name="DeferredTaxAssetsRent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_DeferredTaxLiabilitiesForeignInvestments" name="DeferredTaxLiabilitiesForeignInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_DeferredTaxLiabilityonUnremittedForeignEarnings" name="DeferredTaxLiabilityonUnremittedForeignEarnings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cdw_DescriptionofBusinessPolicyTextBlock" name="DescriptionofBusinessPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_DesktopsMember" name="DesktopsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_DisposalofFullyAmortizedDefiniteLivedIntangibleAssets" name="DisposalofFullyAmortizedDefiniteLivedIntangibleAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_EducationMember" name="EducationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefitAmount" name="EffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefitAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefitPercent" name="EffectiveIncomeTaxRateReconciliationSharebasedCompensationExcessTaxBenefitPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Amount" name="EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Amount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent" name="EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationWithholdingTaxExpenseonUnremittedForeignEarningsasaResultofaChangeinReinvestmentAssertionAmount" name="EffectiveIncomeTaxRateReconciliationWithholdingTaxExpenseonUnremittedForeignEarningsasaResultofaChangeinReinvestmentAssertionAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_EffectiveIncomeTaxRateReconciliationWithholdingTaxExpenseonUnremittedForeignEarningsasaResultofaChangeinReinvestmentAssertionPercent" name="EffectiveIncomeTaxRateReconciliationWithholdingTaxExpenseonUnremittedForeignEarningsasaResultofaChangeinReinvestmentAssertionPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_EmployeeStockPurchasePlandiscounttomarketpricepercent" name="EmployeeStockPurchasePlandiscounttomarketpricepercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_EnterpriseAndDataStorageIncludingDrivesMember" name="EnterpriseAndDataStorageIncludingDrivesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_EquityInEarningsLossOfSubsidiaries" name="EquityInEarningsLossOfSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cdw_Fairvalueofoptionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" name="Fairvalueofoptionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_FixedChargeCoverageRatio" name="FixedChargeCoverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_ForecastedYearsforGoodwillImpairment" name="ForecastedYearsforGoodwillImpairment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_GoodwillImpairmentTestIncomeApproachWeight" name="GoodwillImpairmentTestIncomeApproachWeight" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_GoodwillImpairmentTestMarketApproachWeight" name="GoodwillImpairmentTestMarketApproachWeight" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_GovernmentSegmentMember" name="GovernmentSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_GrossMarginPercent" name="GrossMarginPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_HealthcareMember" name="HealthcareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_IncomeLossBeforeEquityInEarningsLossOfSubsidiaries" name="IncomeLossBeforeEquityInEarningsLossOfSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InterestRateBasisAxis" name="InterestRateBasisAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InterestRateBasisDomain" name="InterestRateBasisDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InventoryFinancingAgreementsAbstract" name="InventoryFinancingAgreementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InventoryFinancingAgreementsAxis" name="InventoryFinancingAgreementsAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InventoryFinancingAgreementsDomain" name="InventoryFinancingAgreementsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InventoryFinancingAgreementsLineItems" name="InventoryFinancingAgreementsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_InventoryFinancingAgreementsTable" name="InventoryFinancingAgreementsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_InventoryFinancingAgreementsTableTextBlock" name="InventoryFinancingAgreementsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_InventoryFinancingAgreementsTextblock" name="InventoryFinancingAgreementsTextblock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_KelwayTopCoLimitedMember" name="KelwayTopCoLimitedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_LiborMember" name="LiborMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_LineOfCreditFacilityBorrowingBase" name="LineOfCreditFacilityBorrowingBase" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LineOfCreditFacilityMaximumAggregateIncrease" name="LineOfCreditFacilityMaximumAggregateIncrease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongTermConsolidatedAnnualGrowthRate" name="LongTermConsolidatedAnnualGrowthRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongTermDebtCurrentMaturitiesNetofDeferredFinancingCostsDiscountorPremium" name="LongTermDebtCurrentMaturitiesNetofDeferredFinancingCostsDiscountorPremium" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongTermDebtNetofDeferredFinancingCostsDiscountorPremium" name="LongTermDebtNetofDeferredFinancingCostsDiscountorPremium" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongtermDebtCurrentMaturitiesGross" name="LongtermDebtCurrentMaturitiesGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongtermDebtExcludingCurrentMaturitiesGross" name="LongtermDebtExcludingCurrentMaturitiesGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_LongtermDebtExcludingCurrentMaturitiesNetofDeferredFinancingCostsDiscountorPremium" name="LongtermDebtExcludingCurrentMaturitiesNetofDeferredFinancingCostsDiscountorPremium" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_ManagementFeeIncomeExpense" name="ManagementFeeIncomeExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="cdw_MarginonBorrowingsReducedInterestRatefromRefinancinginbps" name="MarginonBorrowingsReducedInterestRatefromRefinancinginbps" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_MinimumLiquidityConditionAmount" name="MinimumLiquidityConditionAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_MinimumLiquidityConditionCashAvailability" name="MinimumLiquidityConditionCashAvailability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="cdw_MiscellaneousReceivablesPolicyPolicyTextBlock" name="MiscellaneousReceivablesPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_NetChangeInAccountsPayableInventoryFinancing" name="NetChangeInAccountsPayableInventoryFinancing" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_NetLeverageRatio" name="NetLeverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_NetcommProductsMember" name="NetcommProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_NotebooksMobileDevicesMember" name="NotebooksMobileDevicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_NumberofOperatingSegmentsReportableUnitQuantitativeThresholdNotMet" name="NumberofOperatingSegmentsReportableUnitQuantitativeThresholdNotMet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_NumberofOwnedSubsidiaries" name="NumberofOwnedSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_Optionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" name="Optionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_OtherHardwareMember" name="OtherHardwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_OtherInventoryFinancingAgreements" name="OtherInventoryFinancingAgreements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_OtherProductsAndServicesMember" name="OtherProductsAndServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_OtherlongtermobligationsDomain" name="OtherlongtermobligationsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_PaymentsforProceedsfromIntercompanyLoan" name="PaymentsforProceedsfromIntercompanyLoan" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_PerformanceShareAwardsMember" name="PerformanceShareAwardsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_PotentialVestingPercentageRangeofShares" name="PotentialVestingPercentageRangeofShares" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_PublicAxis" name="PublicAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_PublicDomain" name="PublicDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_PublicMember" name="PublicMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_PublicSegmentGovernmentAgenciesEducationandHealthcareMember" name="PublicSegmentGovernmentAgenciesEducationandHealthcareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_QuarterlyAmortizationPaymentOfOriginalPrincipalPercent" name="QuarterlyAmortizationPaymentOfOriginalPrincipalPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_Restrictionperiodforcommonsharesissued" name="Restrictionperiodforcommonsharesissued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_RevenuenetbyProductandServicePercentage" name="RevenuenetbyProductandServicePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_RevolvingLoanFinancingAgreement" name="RevolvingLoanFinancingAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="cdw_SalesTaxPolicyPolicyTextBlock" name="SalesTaxPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_ScheduleEquityBasedCompensationExpenseTableTextBlock" name="ScheduleEquityBasedCompensationExpenseTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_SegmentReportingCustomerSegmentsCustomerEmployeeHeadcount" name="SegmentReportingCustomerSegmentsCustomerEmployeeHeadcount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_SeniorNotesdue2022Member" name="SeniorNotesdue2022Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_SeniorNotesdue2023Member" name="SeniorNotesdue2023Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_SeniorNotesdue2024Member" name="SeniorNotesdue2024Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_SeniorNotesdue2025Member" name="SeniorNotesdue2025Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_ServicesMember" name="ServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsAttainmentAdjustmentinthePeriod" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsAttainmentAdjustmentinthePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsAttainmentAdjustmentinthePeriodWeightedAverageGrantDateFairValue" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsAttainmentAdjustmentinthePeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_SharebasedCompensationArrangementsbySharebasedPaymentAwardAwardsGrantedatAcquisitionDateExercisePrice" name="SharebasedCompensationArrangementsbySharebasedPaymentAwardAwardsGrantedatAcquisitionDateExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_Sharessoldbycertainsellingstockholders" name="Sharessoldbycertainsellingstockholders" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_SmallBusinessMember" name="SmallBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_SoftwareProductsMember" name="SoftwareProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_StockOptionContractualLife" name="StockOptionContractualLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_StockRepurchaseProgramAdditionalAmountAuthorizedtobeRepurchased" name="StockRepurchaseProgramAdditionalAmountAuthorizedtobeRepurchased" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_SupplementalGuarantorInformationAbstract" name="SupplementalGuarantorInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_SupplementalGuarantorInformationTextBlock" name="SupplementalGuarantorInformationTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpenseBenefit" name="TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateProvisionalIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_TaxCutsAndJobsActOf2017IncompleteAccountingStateIncomeTaxImpactProvisionalIncomeTaxExpenseBenefit" name="TaxCutsAndJobsActOf2017IncompleteAccountingStateIncomeTaxImpactProvisionalIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="cdw_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit" name="TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_TaxCutsAndJobsActOf2017Member" name="TaxCutsAndJobsActOf2017Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_TermLoanMember" name="TermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_TheShareRepurchaseProgramMember" name="TheShareRepurchaseProgramMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="cdw_TotalHardwareMember" name="TotalHardwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_TreasuryStockParOrStatedValuePerShare" name="TreasuryStockParOrStatedValuePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_VariableInterestRateMargin" name="VariableInterestRateMargin" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="cdw_VendorPartnerReceivablesCurrent" name="VendorPartnerReceivablesCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="cdw_VideoMember" name="VideoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_Weightedaverageserviceperiodofoptionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" name="Weightedaverageserviceperiodofoptionsissuedbyoneofthesellerstocertaincoworkersoversharesofthesellerscommonstockreceivedaspartofconsiderationfromacquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="cdw_WriteOffOfDeferredDebtDiscount" name="WriteOffOfDeferredDebtDiscount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
</xsd:schema>
