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  <xsd:element id="lh_FairValueLiabilitiesMeasuredOnRecurringBasisNoncontrollingInterestPuts" name="FairValueLiabilitiesMeasuredOnRecurringBasisNoncontrollingInterestPuts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="lh_Impairmentoffloatingratenotereceivable" name="Impairmentoffloatingratenotereceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_IncomeAbstract" name="IncomeAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_IncomeLossFromContinuingOperationsBeforeIncomeTaxesAndMinorityInterest" name="IncomeLossFromContinuingOperationsBeforeIncomeTaxesAndMinorityInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_IncomeLossfromContinuingOperationsBeforeIncomeTaxesandNoncontrollingInterest" name="IncomeLossfromContinuingOperationsBeforeIncomeTaxesandNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_IncreaseDecreaseinOperatingIncomeLoss" name="IncreaseDecreaseinOperatingIncomeLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_IncreaseDecreaseinUnbilledContractReceivable" name="IncreaseDecreaseinUnbilledContractReceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_Intercompanyrevenueelimination" name="Intercompanyrevenueelimination" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_InterestPaidInCash" name="InterestPaidInCash" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_Issuanceofcommonstockunderemployeeplans" name="Issuanceofcommonstockunderemployeeplans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_LabCorpDiagnosticsMember" name="LabCorpDiagnosticsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_LongTermContractsDurationMaximum" name="LongTermContractsDurationMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_LongTermContractsDurationMinimum" name="LongTermContractsDurationMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_Longtermdebtissuancecosts" name="Longtermdebtissuancecosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_MedicareandMedicaidMember" name="MedicareandMedicaidMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_NetDefinedBenefitPlanAmortizationAndDeferral" name="NetDefinedBenefitPlanAmortizationAndDeferral" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_NetProceedsFromIssuanceOfStockToEmployees" name="NetProceedsFromIssuanceOfStockToEmployees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_NetRestructuringAndOtherSpecialCharges" name="NetRestructuringAndOtherSpecialCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_NetRestructuringCharges" name="NetRestructuringCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_NonElectiveContribution" name="NonElectiveContribution" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_NoncontrollingInterestMezzanineEquity" name="NoncontrollingInterestMezzanineEquity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_NoncontrollingInterestPutsAbstract" name="NoncontrollingInterestPutsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_NoteReceivableAllowanceforCreditLoss" name="NoteReceivableAllowanceforCreditLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="lh_NoteReceivableCreditLossExpenseReversal" name="NoteReceivableCreditLossExpenseReversal" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_NovelCoranvirusCovid19FinancialStatementImpactPolicyTextBlock" name="NovelCoranvirusCovid19FinancialStatementImpactPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_NumberofAdditionalPartiesNotProvidingConsent" name="NumberofAdditionalPartiesNotProvidingConsent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_NumberofMeasurementFundsAvailableForParticipantElection" name="NumberofMeasurementFundsAvailableForParticipantElection" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_OtherFinancingCashFlows" name="OtherFinancingCashFlows" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_OtheracquireesMember" name="OtheracquireesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_OthercountriesMember" name="OthercountriesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_OutstandingStockRepurchaseAuthorizationAbstract" name="OutstandingStockRepurchaseAuthorizationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_PatentsLicensesAndTechnologyMember" name="PatentsLicensesAndTechnologyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_PerShareAmountAbstract" name="PerShareAmountAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_PercentChangeinDiscountRateUsedtoCalculateFairValueofGoodwillforReportingUnit" name="PercentChangeinDiscountRateUsedtoCalculateFairValueofGoodwillforReportingUnit" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_PercentageChangeinDiscountRateUsedtoCalculateFairValueofGoodwill" name="PercentageChangeinDiscountRateUsedtoCalculateFairValueofGoodwill" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_PercentageFairValueofGoodwillExceededCarryingValue" name="PercentageFairValueofGoodwillExceededCarryingValue" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_PercentofFairValueExceedingCarryingValuePostPercentChangeinDiscountRateUsedtoCalculateFairValueofGoodwillforReportingUnit" name="PercentofFairValueExceedingCarryingValuePostPercentChangeinDiscountRateUsedtoCalculateFairValueofGoodwillforReportingUnit" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_PercentofRevenueContributed" name="PercentofRevenueContributed" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_Percentofremainingperformanceobligationsrecognizedasrevenueinnextyear" name="Percentofremainingperformanceobligationsrecognizedasrevenueinnextyear" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_RecentlyAdoptedAccountingGuidancePolicyTextBlock" name="RecentlyAdoptedAccountingGuidancePolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_RestructuringImpairment" name="RestructuringImpairment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_RestructuringReserveSettledWithCashAndOtherAdjustment" name="RestructuringReserveSettledWithCashAndOtherAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_RevolvingCreditFacilityAccrueInterestPerAnnumBaseRatePlusPercentage" name="RevolvingCreditFacilityAccrueInterestPerAnnumBaseRatePlusPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_RevolvingCreditFacilityAccrueInterestperAnnumatLiborPlusMarginPercentage" name="RevolvingCreditFacilityAccrueInterestperAnnumatLiborPlusMarginPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_RevolvingCreditFacilityFeePercentageRequiredtoPayonOutstandingCommitments" name="RevolvingCreditFacilityFeePercentageRequiredtoPayonOutstandingCommitments" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_SalesCommissionAmortizationPeriodMaximum" name="SalesCommissionAmortizationPeriodMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_SalesCommissionAmortizationPeriodMinimum" name="SalesCommissionAmortizationPeriodMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_ScheduleOfOtherIntangibleAssetsByMajorClassAxis" name="ScheduleOfOtherIntangibleAssetsByMajorClassAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_ScheduleOfOtherIntangibleAssetsByMajorClassDomain" name="ScheduleOfOtherIntangibleAssetsByMajorClassDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_ScheduleofBusinessAcquisitionsbyAcquisitionAbstract" name="ScheduleofBusinessAcquisitionsbyAcquisitionAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_SegmentReconciliationofOperatingIncometoConsolidatedAbstract" name="SegmentReconciliationofOperatingIncometoConsolidatedAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_SeniorLongTermNotesDue2020Member" name="SeniorLongTermNotesDue2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_SeniorNotesBecameDueDuringQuarter" name="SeniorNotesBecameDueDuringQuarter" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_SeniorNotesDue2020Member" name="SeniorNotesDue2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_SeniorNotesDue2022Member" name="SeniorNotesDue2022Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_SeniorNotesFairValue" name="SeniorNotesFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_Seniornotesdue2023Member" name="Seniornotesdue2023Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_Seniornotesdue2024MemberMember" name="Seniornotesdue2024MemberMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_Seniornotesdue2025MemberMember" name="Seniornotesdue2025MemberMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_Seniornotesdue2027Member" name="Seniornotesdue2027Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_Seniornotesdue2045Member" name="Seniornotesdue2045Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_SharesAbstract" name="SharesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_Shorttermdebtissuancecosts" name="Shorttermdebtissuancecosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="lh_TermLoanAccrueInterestPerAnnumBaseRatePlusPercentage" name="TermLoanAccrueInterestPerAnnumBaseRatePlusPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="lh_TermLoanAccrueInterestperAnnumatLiborPlusMarginPercentage" name="TermLoanAccrueInterestperAnnumatLiborPlusMarginPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_TermLoanandRevolvingCreditFacilityMember" name="TermLoanandRevolvingCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_ThirdpartyMember" name="ThirdpartyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_Totalacquisitionconsiderationcashstocknotesetc." name="Totalacquisitionconsiderationcashstocknotesetc." nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_UnbilledContractsReceivableMember" name="UnbilledContractsReceivableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="lh_UnbilledServicesAllowanceforCreditLoss" name="UnbilledServicesAllowanceforCreditLoss" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="lh_UnbilledServicesCreditLossExpenseReversal" name="UnbilledServicesCreditLossExpenseReversal" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_Unusedfacilityrestructuringreserves" name="Unusedfacilityrestructuringreserves" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="lh_ValueofGoodwillImpairmentFollowingaPercentageChangeintheDiscountRateUsedtoCalculateGoodwillforReportingUnit" name="ValueofGoodwillImpairmentFollowingaPercentageChangeintheDiscountRateUsedtoCalculateGoodwillforReportingUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="lh_ValueofReportingUnitsGoodwillFairValueExceedsCarryingValue" name="ValueofReportingUnitsGoodwillFairValueExceedsCarryingValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="lh_ValueofReportingUnitsGoodwillFollowingImpairment" name="ValueofReportingUnitsGoodwillFollowingImpairment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="lh_ZeroCouponConvertibleSubordinatedNotesLineItems" name="ZeroCouponConvertibleSubordinatedNotesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="lh_ZeroCouponConvertibleSubordinatedNotesTable" name="ZeroCouponConvertibleSubordinatedNotesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
</xsd:schema>
