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  <xsd:element id="mck_BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGainNetOfIncomeTaxes" name="BusinessCombinationStepAcquisitionEquityInterestInAcquireeRemeasurementGainNetOfIncomeTaxes" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_CanadaRevenueAgencyAssessmentsMember" name="CanadaRevenueAgencyAssessmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_CapitalizedComputerSoftwareForeignCurrencyTranslationsAdjustmentsNet" name="CapitalizedComputerSoftwareForeignCurrencyTranslationsAdjustmentsNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_CapitalizedSoftwareHeldForSaleTableTextBlock" name="CapitalizedSoftwareHeldForSaleTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_CapitalizedSoftwareHeldforInternalUseUsefulLife" name="CapitalizedSoftwareHeldforInternalUseUsefulLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_CapitalizedSoftwareHeldforSaleUsefulLife" name="CapitalizedSoftwareHeldforSaleUsefulLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_CelesioMember" name="CelesioMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesIncreaseInPaidInCapital" name="ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesIncreaseInPaidInCapital" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentCommonShares" name="ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentCommonShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentConsiderationPaid" name="ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentConsiderationPaid" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentPercent" name="ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestChangesPurchaseOfInterestByParentPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ContingentPurchaseOfferSeries" name="ContingentPurchaseOfferSeries" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_ControlledSubstanceInvestigationMember" name="ControlledSubstanceInvestigationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_CorporateHeadquartersMember" name="CorporateHeadquartersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_CurrentAndNonCurrentReceivablesMember" name="CurrentAndNonCurrentReceivablesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_CurrentlyAcquiredPercentageOfBuilding" name="CurrentlyAcquiredPercentageOfBuilding" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mck_DataRelatedtoRSUActivityTableTextBlock" name="DataRelatedtoRSUActivityTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DeferredTaxLiabilitiesGrossNetByJurisdiction" name="DeferredTaxLiabilitiesGrossNetByJurisdiction" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mck_DefinedBenefitPlanActuarialLossesPercentageExceedingGreaterOfProjectedBenefitObligationOrMarketValueOfAssets" name="DefinedBenefitPlanActuarialLossesPercentageExceedingGreaterOfProjectedBenefitObligationOrMarketValueOfAssets" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="mck_DefinedBenefitPlanAmortizationofActuarialLossPriorServiceCostandTransitionObligationIncomeTaxExpenseBenefit" name="DefinedBenefitPlanAmortizationofActuarialLossPriorServiceCostandTransitionObligationIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanAmortizationofGainsLossesPriorServiceCostCreditandTransitionObligationsAssets" name="DefinedBenefitPlanAmortizationofGainsLossesPriorServiceCostCreditandTransitionObligationsAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanAmortizationofunrecognizedactuarialgainandpriorservicecost" name="DefinedBenefitPlanAmortizationofunrecognizedactuarialgainandpriorservicecost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedBenefitPlanAssumptionsUsedAxis" name="DefinedBenefitPlanAssumptionsUsedAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRates" name="DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRates" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationChangeInRateBasisPoints" name="DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationChangeInRateBasisPoints" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedBenefitPlanAssumptionsUsedDomain" name="DefinedBenefitPlanAssumptionsUsedDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanBenefitsPaidNetofContribution" name="DefinedBenefitPlanBenefitsPaidNetofContribution" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanContributionsbyEmployerandPlanParticipants" name="DefinedBenefitPlanContributionsbyEmployerandPlanParticipants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanDisclosuresByHealthcareCostTrendsDomain" name="DefinedBenefitPlanDisclosuresByHealthcareCostTrendsDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanEmployerContributionsPercentExceedPlanAsset" name="DefinedBenefitPlanEmployerContributionsPercentExceedPlanAsset" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsBeginning2015" name="DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsBeginning2015" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mck_DefinedBenefitPlanHighestAveragePayMonths" name="DefinedBenefitPlanHighestAveragePayMonths" nillable="true" substitutionGroup="xbrli:item" type="us-types:durationStringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedBenefitPlanParticipantAgeRangeAxis" name="DefinedBenefitPlanParticipantAgeRangeAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedBenefitPlanParticipantAgeRangeDomain" name="DefinedBenefitPlanParticipantAgeRangeDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanPlansObligationsInExcessOfPlanAssetShortfallPercent" name="DefinedBenefitPlanPlansObligationsInExcessOfPlanAssetShortfallPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanPlansObligationsInExcessOfPlanAssetShortfallRemedyPeriod" name="DefinedBenefitPlanPlansObligationsInExcessOfPlanAssetShortfallRemedyPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanPostretirementWelfareBenefitPlanActuarialGainLossAmortizationPeriodDefined" name="DefinedBenefitPlanPostretirementWelfareBenefitPlanActuarialGainLossAmortizationPeriodDefined" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DefinedBenefitPlanYearsPriorToFreezeDate" name="DefinedBenefitPlanYearsPriorToFreezeDate" nillable="true" substitutionGroup="xbrli:item" type="us-types:durationStringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedContributionPlanMatchingAxis" name="DefinedContributionPlanMatchingAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DefinedContributionPlanMatchingDomain" name="DefinedContributionPlanMatchingDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_DentalMember" name="DentalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DistributionSolutionsMedicalSurgicalDistributionAndServicesMember" name="DistributionSolutionsMedicalSurgicalDistributionAndServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DistributionSolutionsMember" name="DistributionSolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_EarningsPerShareBasicEffectOfDilutiveSecuritiesAxis" name="EarningsPerShareBasicEffectOfDilutiveSecuritiesAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_EarningsPerShareBasicEffectOfDilutiveSecuritiesDomain" name="EarningsPerShareBasicEffectOfDilutiveSecuritiesDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_EffectiveIncomeTaxRateReconciliationDiscreteItems" name="EffectiveIncomeTaxRateReconciliationDiscreteItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_EmployeeContributions" name="EmployeeContributions" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_EmployeeServiceShareBasedCompensationPeriodToPurchaseSharesThroughPayrollDeductions" name="EmployeeServiceShareBasedCompensationPeriodToPurchaseSharesThroughPayrollDeductions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_EnvironmentalLitigationMember" name="EnvironmentalLitigationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_EquityMethodInvestmentandJointVentureDisclosureAbstract" name="EquityMethodInvestmentandJointVentureDisclosureAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_EstimatedEnvironmentalAssessmentAndCleanupCosts" name="EstimatedEnvironmentalAssessmentAndCleanupCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_FinancialGuaranteesAndWarrantiesAbstract" name="FinancialGuaranteesAndWarrantiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_FinancialGuaranteesAndWarrantiesTextBlock" name="FinancialGuaranteesAndWarrantiesTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_FirstPartOfPayContributionMember" name="FirstPartOfPayContributionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_FivePointSevenZeroPercentNotesDueMarchOneTwoThousandSeventeenMember" name="FivePointSevenZeroPercentNotesDueMarchOneTwoThousandSeventeenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_FivePointTwoFivePercentNotesDueMarchOneTwoThousandThirteenMember" name="FivePointTwoFivePercentNotesDueMarchOneTwoThousandThirteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember" name="FloatingRateNotesDueSeptemberTenthTwoThousandFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember" name="FourPercentBondsDueOctoberEighteenTwoThousandSixteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember" name="FourPointEightEightPercentNotesDueMarchFifteenthTwoThousandFortyFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember" name="FourPointFivePercentBondsDueAprilTwentySixTwoThousandSeventeenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_FourPointSevenFivePercentNotesDuesMarchOneTwoThousandTwentyOneMember" name="FourPointSevenFivePercentNotesDuesMarchOneTwoThousandTwentyOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_GuaranteeObligationsCustomersDebtMember" name="GuaranteeObligationsCustomersDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearFive" name="GuaranteeObligationsExposureExpiringinYearFive" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearFiveThereafter" name="GuaranteeObligationsExposureExpiringinYearFiveThereafter" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearFour" name="GuaranteeObligationsExposureExpiringinYearFour" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearOne" name="GuaranteeObligationsExposureExpiringinYearOne" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearThree" name="GuaranteeObligationsExposureExpiringinYearThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteeObligationsExposureExpiringinYearTwo" name="GuaranteeObligationsExposureExpiringinYearTwo" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_GuaranteeObligationsInventoryRepurchaseGuaranteesMember" name="GuaranteeObligationsInventoryRepurchaseGuaranteesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_GuaranteedDividend" name="GuaranteedDividend" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="mck_GuaranteedDividendAmount" name="GuaranteedDividendAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_GuaranteeofInvesteeBuildinganEquipmentConstructionMember" name="GuaranteeofInvesteeBuildinganEquipmentConstructionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_HazardousSubstanceSites" name="HazardousSubstanceSites" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_HospitalAutomationMember" name="HospitalAutomationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ImpairmentinExcessofCarryingValue" name="ImpairmentinExcessofCarryingValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mck_IncomeTaxBenefitDiscreteItems" name="IncomeTaxBenefitDiscreteItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_InsuranceProgramsPolicyTextBlock" name="InsuranceProgramsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_InternationalDistributionandServicesMember" name="InternationalDistributionandServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_InternationalTechnologyMember" name="InternationalTechnologyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_InternationalTechnologySoftwareMember" name="InternationalTechnologySoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_InternationalTechnologyWorkforceMember" name="InternationalTechnologyWorkforceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_InventoryLIFOtoMarketAdjustment" name="InventoryLIFOtoMarketAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_LargestCustomerMember" name="LargestCustomerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_LossContingencyLossinPeriodNetofTax" name="LossContingencyLossinPeriodNetofTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_LossContingencyNumberofAdditionalDefendants" name="LossContingencyNumberofAdditionalDefendants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_LossContingencyNumberofRelators" name="LossContingencyNumberofRelators" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_LossContingencyNumberofStatesFiledOnBehalfOf" name="LossContingencyNumberofStatesFiledOnBehalfOf" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_MarketBasedPerformanceSharesMember" name="MarketBasedPerformanceSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_MedicalMember" name="MedicalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_MulitemployerPlanFundedStatusPercentage" name="MulitemployerPlanFundedStatusPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mck_NadroMember" name="NadroMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_NetIncomeLossAttributabletoNoncontrollingInterestsExcludingRedeemableNoncontrollingInterests" name="NetIncomeLossAttributabletoNoncontrollingInterestsExcludingRedeemableNoncontrollingInterests" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_NetIncomeLossIncludingPortionAttributabletoNoncontrollingInterestExcludingRedeemableNoncontrollingInterest" name="NetIncomeLossIncludingPortionAttributabletoNoncontrollingInterestExcludingRedeemableNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_NoncontrollingInterestsChangesOther" name="NoncontrollingInterestsChangesOther" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_NorthAmericaDistributionAndServicesMember" name="NorthAmericaDistributionAndServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_NorwegianPublicServicePensionFundSPKMember" name="NorwegianPublicServicePensionFundSPKMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_NumberOfDaysNoticeBeforeNotesCanBeRedeemed" name="NumberOfDaysNoticeBeforeNotesCanBeRedeemed" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember" name="OnePointFourZeroPercentNotesDueMarchFifteenthTwoThousandEighteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember" name="OnePointTwoNinePercentNotesDueMarchTenthTwoThousandSeventeenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherAllowancesMember" name="OtherAllowancesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherCommingledFundsMember" name="OtherCommingledFundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherComprehensiveIncomeDefinedBenefitPlansNetTranslationGainLossArisingDuringPeriodBeforeTax" name="OtherComprehensiveIncomeDefinedBenefitPlansNetTranslationGainLossArisingDuringPeriodBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherComprehensiveIncomeLossIncludingPortionAttributabletoNoncontrollingInterestsNetofTax" name="OtherComprehensiveIncomeLossIncludingPortionAttributabletoNoncontrollingInterestsNetofTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherComprehensiveIncomeLossNetOfTaxExcludingRedeemableNoncontrollingInterest" name="OtherComprehensiveIncomeLossNetOfTaxExcludingRedeemableNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherComprehensiveIncomeTranslationImpactOnPensionPlansNetOfTax" name="OtherComprehensiveIncomeTranslationImpactOnPensionPlansNetOfTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherComprehensiveIncomeTranslationImpactOnPensionPlansTax" name="OtherComprehensiveIncomeTranslationImpactOnPensionPlansTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_OtherLongTermDebtMember" name="OtherLongTermDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_OtherfundsMember" name="OtherfundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PensionAndOtherPostretirementDefinedBenefitPlansPlanAssetValue" name="PensionAndOtherPostretirementDefinedBenefitPlansPlanAssetValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mck_PensionPlansExcludingOtherPostretirementBenefitPlansMember" name="PensionPlansExcludingOtherPostretirementBenefitPlansMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligation" name="PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligation" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligationAgeThreshold" name="PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligationAgeThreshold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligationAxis" name="PensionandOtherPostretirementBenefitPlansAssumptionsUsedCalculatingPostretirementBenefitObligationAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_PensjonsordningenforApoteketatenPOAMember" name="PensjonsordningenforApoteketatenPOAMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PercentageOfRevenueDerivedFromServices" name="PercentageOfRevenueDerivedFromServices" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_PharmacyLicensesMember" name="PharmacyLicensesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_Post65MedicalMember" name="Post65MedicalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_Pre65MedicalMember" name="Pre65MedicalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PrescriptionDrugsMember" name="PrescriptionDrugsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_ProductAlignmentByTypeAxis" name="ProductAlignmentByTypeAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_ProductAlignmentByTypeDomain" name="ProductAlignmentByTypeDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ProductAlignmentCharges" name="ProductAlignmentCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_PromissoryNotesMember" name="PromissoryNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_PssWorldMedicalMember" name="PssWorldMedicalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_PutOptionforNCIUnderDominationAgreementCelesioPerShare" name="PutOptionforNCIUnderDominationAgreementCelesioPerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="mck_PutRightInterestRate" name="PutRightInterestRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mck_QuarterlyFinancialInformationLineItems" name="QuarterlyFinancialInformationLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_QuarterlyFinancialInformationTable" name="QuarterlyFinancialInformationTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_RangeOneMember" name="RangeOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_RangeTwoMember" name="RangeTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ReceivableMember" name="ReceivableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ReclassificationfromEquitytoLiability" name="ReclassificationfromEquitytoLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_ReclassificationfromPermanentEquity" name="ReclassificationfromPermanentEquity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_ReclassificationofTemporaryEquitytoLiability" name="ReclassificationofTemporaryEquitytoLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_ReclassificationtoTemporaryEquity" name="ReclassificationtoTemporaryEquity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_RecurringCompensationtoRedeemableNoncontrollingInterests" name="RecurringCompensationtoRedeemableNoncontrollingInterests" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_RedeemableNoncontrollingInterestsMaximumRedemptionValue" name="RedeemableNoncontrollingInterestsMaximumRedemptionValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mck_RedeemableNoncontrollingInterestsRollforwardAbstract" name="RedeemableNoncontrollingInterestsRollforwardAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardDataRelatedToStockOptionActivityTableTextBlock" name="ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardDataRelatedToStockOptionActivityTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ScheduleofChangesInNoncontrollingInterestsTableTextBlock" name="ScheduleofChangesInNoncontrollingInterestsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SecondPartOfPayContributionMember" name="SecondPartOfPayContributionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeniorBridgeTermLoanAgreement2013Member" name="SeniorBridgeTermLoanAgreement2013Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeniorBridgeTermLoanAgreement2014Member" name="SeniorBridgeTermLoanAgreement2014Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeniorConvertibleNotesDue2014Member" name="SeniorConvertibleNotesDue2014Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeniorNotesDue2022AndSeniorConvertibleNotesDue214Member" name="SeniorNotesDue2022AndSeniorConvertibleNotesDue214Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeniorNotesDue2022Member" name="SeniorNotesDue2022Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SensitivityAnalysisOfNetPeriodicPensionCostImpactOfOnePercentagePointDecreaseInDiscountRate" name="SensitivityAnalysisOfNetPeriodicPensionCostImpactOfOnePercentagePointDecreaseInDiscountRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_SensitivityAnalysisOfNetPeriodicPensionCostImpactOfOnePercentagePointIncreaseInDiscountRate" name="SensitivityAnalysisOfNetPeriodicPensionCostImpactOfOnePercentagePointIncreaseInDiscountRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mck_SensitivityAnalysisOfProjectedBenefitObligationsImpactOfOnePercentagePointDecreaseInDiscountRate" name="SensitivityAnalysisOfProjectedBenefitObligationsImpactOfOnePercentagePointDecreaseInDiscountRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_SensitivityAnalysisOfProjectedBenefitObligationsImpactOfOnePercentagePointIncreaseInDiscountRate" name="SensitivityAnalysisOfProjectedBenefitObligationsImpactOfOnePercentagePointIncreaseInDiscountRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="mck_SevenPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandNineteenMember" name="SevenPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandNineteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SevenPointSixFivePercentDebenturesDueMarchOneTwoThousandTwentySevenMember" name="SevenPointSixFivePercentDebenturesDueMarchOneTwoThousandTwentySevenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SeveranceChargesDuetoReorganizationMember" name="SeveranceChargesDuetoReorganizationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SiteContingencyNumberOfSites" name="SiteContingencyNumberOfSites" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SixPercentNotesDueMarchOneTwoThousandFortyOneMember" name="SixPercentNotesDueMarchOneTwoThousandFortyOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SixPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandFourteenMember" name="SixPointFiveZeroPercentNotesDueFebruaryFifteenTwoThousandFourteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_StockholdersEquityTable" name="StockholdersEquityTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_SupplierReserves" name="SupplierReserves" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mck_SupplierReservesPolicyTextBlock" name="SupplierReservesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_TaxRecognizedPercentLikelyBeingRealized" name="TaxRecognizedPercentLikelyBeingRealized" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_TechnologySolutionsMember" name="TechnologySolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_TermLoanMember" name="TermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember" name="ThreePointEightZeroPercentNotesDueMarchFifteenthTwoThousandTwentyFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ThreePointTwoFivePercentNotesDueMarchOneTwoThousandSixteenMember" name="ThreePointTwoFivePercentNotesDueMarchOneTwoThousandSixteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_TreasuryStockAcquiredNetofRetirementsAmount" name="TreasuryStockAcquiredNetofRetirementsAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember" name="TwoPointEightFivePercentNotesDueMarchFifteenTwoThousandTwentyThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember" name="TwoPointSevenZeroPercentNotesDueDecemberFifteenTwoThousandTwentyTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember" name="TwoPointTwoEightNotesDueMarchFifteenthTwoThousandNineteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_UnfundedplanMember" name="UnfundedplanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_UnitValueOfCashAndCashEquivalents" name="UnitValueOfCashAndCashEquivalents" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_UnitedStatesDefinedContributionPensionMember" name="UnitedStatesDefinedContributionPensionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ValuationAllowancesAndReservesDeductionsCreditedToOtherAccountsMember" name="ValuationAllowancesAndReservesDeductionsCreditedToOtherAccountsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_ValuationAllowancesAndReservesDeductionsWrittenOffMember" name="ValuationAllowancesAndReservesDeductionsWrittenOffMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mck_VariableinterestentitiesTextBlock" name="VariableinterestentitiesTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mck_ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember" name="ZeroPointNineFivePercentNotesDueDecemberFourTwoThousandFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
