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  <xs:element id="ldos_TransitionCostsandProjectAssetsNetCurrent" abstract="false" name="TransitionCostsandProjectAssetsNetCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_SuretyBondsOutstandingNotionalAmount" abstract="false" name="SuretyBondsOutstandingNotionalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" abstract="true" name="CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_TheCreditAgreementMember" abstract="true" name="TheCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_VehicleAndTransportationEquipmentMember" abstract="true" name="VehicleAndTransportationEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_CobhamAviationServicesMember" abstract="true" name="CobhamAviationServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_NoncurrentLeaseLiabilitiesAbstract" abstract="true" name="NoncurrentLeaseLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_AcquisitionIntegrationAndRestructuringCosts" abstract="false" name="AcquisitionIntegrationAndRestructuringCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" abstract="true" name="InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_DebtInstrumentIncreaseInCommercialPaperProgram" abstract="false" name="DebtInstrumentIncreaseInCommercialPaperProgram" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsCapitalizedResearchAndDevelopment" abstract="false" name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnDecemberTwoThousandFortyMember" abstract="true" name="NotesWhichMatureOnDecemberTwoThousandFortyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_LeaseLiabilityNoncurrent" abstract="false" name="LeaseLiabilityNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GuaranteedObligationTypeDomain" abstract="true" name="GuaranteedObligationTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearTwo" abstract="false" name="GuaranteedObligationMaturityYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_SignificantAccountingPoliciesLineItems" abstract="true" name="SignificantAccountingPoliciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_LeaseRightOfUseAsset" abstract="false" name="LeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnFebruaryTwoThousandThirtyOneMember" abstract="true" name="NotesWhichMatureOnFebruaryTwoThousandThirtyOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationImpactOfGoodwill" abstract="false" name="EffectiveIncomeTaxRateReconciliationImpactOfGoodwill" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GuaranteedObligationFiscalYearMaturityTableTextBlock" abstract="false" name="GuaranteedObligationFiscalYearMaturityTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="ldos_DebtInstrumentCovenantConsolidatedEBITDAToInterestExpenseRatio" abstract="false" name="DebtInstrumentCovenantConsolidatedEBITDAToInterestExpenseRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="ldos_MaximumPercentageThatWillUltimatelyVestForSharesProvidedUnderLongTermPerformanceBasedIncentiveEquityAwardsBasedOnTargetAmountStatedInAgreement" abstract="false" name="MaximumPercentageThatWillUltimatelyVestForSharesProvidedUnderLongTermPerformanceBasedIncentiveEquityAwardsBasedOnTargetAmountStatedInAgreement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="ldos_CurrentLeaseLiabilitiesAbstract" abstract="true" name="CurrentLeaseLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" abstract="true" name="NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_NonCashGoodwillImpairmentCharge" abstract="false" name="NonCashGoodwillImpairmentCharge" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TermLoanDueMarchTwoThousandThirtyThreeMember" abstract="true" name="TermLoanDueMarchTwoThousandThirtyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_TermLoanDueMarchTwentyThousandTwentyEightMember" abstract="true" name="TermLoanDueMarchTwentyThousandTwentyEightMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearThree" abstract="false" name="GuaranteedObligationMaturityYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_CostReimbursementAndFixedPriceIncentiveFeeMember" abstract="true" name="CostReimbursementAndFixedPriceIncentiveFeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_SummaryofIncomeTaxRelatedBalanceonBalanceSheetTableTextBlock" abstract="false" name="SummaryofIncomeTaxRelatedBalanceonBalanceSheetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="ldos_DefenseSolutionsSegmentMember" abstract="true" name="DefenseSolutionsSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_DebtInstrumentTermExtension" abstract="false" name="DebtInstrumentTermExtension" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ldos_DebtInstrumentMinimumDenominationsUponIssuance" abstract="false" name="DebtInstrumentMinimumDenominationsUponIssuance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AcceleratedShareRepurchaseMember" abstract="true" name="AcceleratedShareRepurchaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnMayTwoThousandTwentyThreeMember" abstract="true" name="NotesWhichMatureOnMayTwoThousandTwentyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_PrepaidTaxesandTaxRefundReceivable" abstract="false" name="PrepaidTaxesandTaxRefundReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TransitionCostsandProjectAssetsNetNoncurrent" abstract="false" name="TransitionCostsandProjectAssetsNetNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AssetImpairmentChargesExcludingGoodwill" abstract="false" name="AssetImpairmentChargesExcludingGoodwill" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_IncreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" abstract="false" name="IncreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_UkPlanMember" abstract="true" name="UkPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_DefenseSolutionMember" abstract="true" name="DefenseSolutionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatio" abstract="false" name="DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="ldos_LeaseLiabilityCurrent" abstract="false" name="LeaseLiabilityCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LiabilityForUncertainTaxPositions" abstract="false" name="LiabilityForUncertainTaxPositions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_StandbyLettersOfCreditSuretyBondsAndFutureLeaseCommitmentsMember" abstract="true" name="StandbyLettersOfCreditSuretyBondsAndFutureLeaseCommitmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GainContingencyPatentsFoundInfringedNumberOther" abstract="false" name="GainContingencyPatentsFoundInfringedNumberOther" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_LeaseliabilitiesarisingfromobtainingROUassetsAbstract" abstract="true" name="LeaseliabilitiesarisingfromobtainingROUassetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_OperatingCyclePolicyPolicyTextBlock" abstract="false" name="OperatingCyclePolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="ldos_A1901GroupMember" abstract="true" name="A1901GroupMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationTypeAxis" abstract="true" name="GuaranteedObligationTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="ldos_HealthSegmentMember" abstract="true" name="HealthSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="ldos_DisclosureScheduleOfCertainFinancialStatementCaptionsAbstract" abstract="true" name="DisclosureScheduleOfCertainFinancialStatementCaptionsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_NumberofDeferredCompensationPlans" abstract="false" name="NumberofDeferredCompensationPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_GuaranteedObligationTypeLineItems" abstract="true" name="GuaranteedObligationTypeLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
</xs:schema>
