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  <xsd:element id="ofc_LeaseRightofUseAssets" name="LeaseRightofUseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
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  <xsd:element id="ofc_LesseeLeaseLiabilityPaymentsDueNextTwelveMonths" name="LesseeLeaseLiabilityPaymentsDueNextTwelveMonths" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
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  <xsd:element id="ofc_LesseeLeaseLiabilityPaymentsDueafterYearFive" name="LesseeLeaseLiabilityPaymentsDueafterYearFive" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ofc_LesseeLeaseLiabilityPaymentsRemainderofFiscalYear" name="LesseeLeaseLiabilityPaymentsRemainderofFiscalYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
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  <xsd:element id="ofc_LesseeNumberOfLeaseContracts" name="LesseeNumberOfLeaseContracts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="ofc_LesseeRemainingTermofContract" name="LesseeRemainingTermofContract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_LesseeRenewalTerm" name="LesseeRenewalTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_LesseeRightofUseAsset" name="LesseeRightofUseAsset" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="ofc_LessorOperatingLeaseAverageTermofContract" name="LessorOperatingLeaseAverageTermofContract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_LineofCreditFacilityAvailableCapacityUnderNewLoansSubjecttoCertainConditions" name="LineofCreditFacilityAvailableCapacityUnderNewLoansSubjecttoCertainConditions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ofc_LineofCreditFacilityExtensionFeePercentage" name="LineofCreditFacilityExtensionFeePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_LineofCreditFacilityMaturityDateExtensionNumberofExtensions" name="LineofCreditFacilityMaturityDateExtensionNumberofExtensions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ofc_LwRedstoneCompanyLlcMember" name="LwRedstoneCompanyLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_MSquareAssociatesLlcMember" name="MSquareAssociatesLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_MaximumAdditionalCostsAgreedToBePaidByTheEntityUnderEnvironmentalIndemnificationAgreement" name="MaximumAdditionalCostsAgreedToBePaidByTheEntityUnderEnvironmentalIndemnificationAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="ofc_MinorityInterestDecreaseFromDistributionsIncludingJointVentures" name="MinorityInterestDecreaseFromDistributionsIncludingJointVentures" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_MinorityInterestDecreaseFromDistributionsToOperatingPartnershipNoncontrollingInterestHolders" name="MinorityInterestDecreaseFromDistributionsToOperatingPartnershipNoncontrollingInterestHolders" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_MinorityInterestInNetIncomeLossOtherIncludingJointVenturesMinorityInterests" name="MinorityInterestInNetIncomeLossOtherIncludingJointVenturesMinorityInterests" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_MinorityInterestIncreaseFromContributionsIncludingJointVentures" name="MinorityInterestIncreaseFromContributionsIncludingJointVentures" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_NewlyConstructedPropertiesPlacedInServiceMember" name="NewlyConstructedPropertiesPlacedInServiceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_NorthernVirginiaMember" name="NorthernVirginiaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_NoteReceivableTermsInterestRate" name="NoteReceivableTermsInterestRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ofc_NotesReceivableFromCityOfHuntsvilleMember" name="NotesReceivableFromCityOfHuntsvilleMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_NumberOfPercentileRanksToFallBetweenToEarnInterpolatedPsu" name="NumberOfPercentileRanksToFallBetweenToEarnInterpolatedPsu" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_NumberofJointVenturesWithRedeemableNoncontrollingInterests" name="NumberofJointVenturesWithRedeemableNoncontrollingInterests" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OfficePropertiesMember" name="OfficePropertiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OperatingLeaseLiabilityMember" name="OperatingLeaseLiabilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OperatingLeaseRightofuseAssetsMember" name="OperatingLeaseRightofuseAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_OtherLandMember" name="OtherLandMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OtherMarketableSecuritiesMember" name="OtherMarketableSecuritiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_OtherPropertyRevenueMember" name="OtherPropertyRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OtherServicesRevenueMember" name="OtherServicesRevenueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_OwnershipInSubsidiaryPercentageLineItems" name="OwnershipInSubsidiaryPercentageLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PartiallyOperationalPropertiesMember" name="PartiallyOperationalPropertiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_PaymentsofLeaseIncentives" name="PaymentsofLeaseIncentives" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PerformancebasedPIUsMember" name="PerformancebasedPIUsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_PrepaidExpensesAndOtherAssetsTextBlock" name="PrepaidExpensesAndOtherAssetsTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PrepaidExpensesandOtherAssetsNetMember" name="PrepaidExpensesandOtherAssetsNetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_ProjectsInDevelopmentOrHeldForFutureDevelopmentMember" name="ProjectsInDevelopmentOrHeldForFutureDevelopmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PropertiesUnderConstructionOrContractuallyCommitedForConstructionMember" name="PropertiesUnderConstructionOrContractuallyCommitedForConstructionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PropertiesUnderConstructionRedevelopmentorContractuallyCommittedforConstructionMember" name="PropertiesUnderConstructionRedevelopmentorContractuallyCommittedforConstructionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PropertiesUnderConstructionorContractuallyCommittedPartiallyOperationalMember" name="PropertiesUnderConstructionorContractuallyCommittedPartiallyOperationalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PropertiesUnderorApprovedforRedevelopmentMember" name="PropertiesUnderorApprovedforRedevelopmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_PropertyOperatingExpenseMember" name="PropertyOperatingExpenseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element id="ofc_PropertySubjecttoEnvironmentalIndemnityNumberofProperties" name="PropertySubjecttoEnvironmentalIndemnityNumberofProperties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ofc_RealEstateJointVentureLineItems" name="RealEstateJointVentureLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_RealEstateJointVenturesDisclosureTextBlock" name="RealEstateJointVenturesDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RealEstateJointVenturesTable" name="RealEstateJointVenturesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RealEstateOperationsMember" name="RealEstateOperationsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_RealEstatePropertyClassificationAxis" name="RealEstatePropertyClassificationAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RealEstatePropertyClassificationDomain" name="RealEstatePropertyClassificationDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ReconciliationofNOIfromRealEstateOperationsandNOIfromServiceOperationstoNetIncomeTableTextBlock" name="ReconciliationofNOIfromRealEstateOperationsandNOIfromServiceOperationstoNetIncomeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_ReconciliationofOperatingIncomefromUnconsolidatedJointVenturestoEquityMethodInvestmentsAbstract" name="ReconciliationofOperatingIncomefromUnconsolidatedJointVenturestoEquityMethodInvestmentsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RedeemableNoncontrollingInterestMember" name="RedeemableNoncontrollingInterestMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RedstoneArsenalMember" name="RedstoneArsenalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RegionalOfficeMember" name="RegionalOfficeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_RestrictedStockandDeferredSharesMember" name="RestrictedStockandDeferredSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_RevenueRemainingPerformanceObligationAmounttobeRecognizedDuringtheRemainderoftheYear" name="RevenueRemainingPerformanceObligationAmounttobeRecognizedDuringtheRemainderoftheYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="ofc_RevenuesFromRealEstateOperationsReceived" name="RevenuesFromRealEstateOperationsReceived" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_RightofUseAssetContributedByNoncontrollingInterest" name="RightofUseAssetContributedByNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_RightofUseAssetsandLeaseLiabilitiesTableTextBlock" name="RightofUseAssetsandLeaseLiabilitiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_ScheduleOfLimitedLiabilityCompanyLlcOrLimitedPartnershipLpManagingMemberOrGeneralPartnerOwnershipInterestTable" name="ScheduleOfLimitedLiabilityCompanyLlcOrLimitedPartnershipLpManagingMemberOrGeneralPartnerOwnershipInterestTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleOfMortgageAndOtherInvestingReceivablesTableTextBlock" name="ScheduleOfMortgageAndOtherInvestingReceivablesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleOfNetOperatingIncomeFromSegmentsFromServiceOperationsTableTextBlock" name="ScheduleOfNetOperatingIncomeFromSegmentsFromServiceOperationsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleOfOperatingPropertiesTableTextBlock" name="ScheduleOfOperatingPropertiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleOfProjectsInDevelopmentOrHeldForFutureDevelopmentTableTextBlock" name="ScheduleOfProjectsInDevelopmentOrHeldForFutureDevelopmentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_ScheduleOfRealEstateTable" name="ScheduleOfRealEstateTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardForDefinedPerformanceTableTextBlock" name="ScheduleOfShareBasedCompensationArrangementByShareBasedPaymentAwardForDefinedPerformanceTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduledPrincipalAmortizationRepaymentsOfLongTermDebt" name="ScheduledPrincipalAmortizationRepaymentsOfLongTermDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="ofc_ScheduleofReconciliationofUnconsolidatedJointVentureNetOperatingIncometoEquityinIncomeofUnconsolidatedEntitiesTableTextBlock" name="ScheduleofReconciliationofUnconsolidatedJointVentureNetOperatingIncometoEquityinIncomeofUnconsolidatedEntitiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedAbstract" name="SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_SegmentReportingRevenueReconcilingItemAbstract" name="SegmentReportingRevenueReconcilingItemAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SegmentReportingTransfersFromNonOperatingProperties" name="SegmentReportingTransfersFromNonOperatingProperties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
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  <xsd:element abstract="true" id="ofc_ServiceOperationsMember" name="ServiceOperationsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEarnedPerformanceShareUnitsPayoutPercentageAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEarnedPerformanceShareUnitsPayoutPercentageAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodAggregateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodAggregateFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="ofc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsBaselineCommonShareValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsBaselineCommonShareValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardDistributionRightsasaPercentageofNonPIUCommonUnitsPercentage" name="SharebasedCompensationArrangementbySharebasedPaymentAwardDistributionRightsasaPercentageofNonPIUCommonUnitsPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsSharesissuedforAwardsVestedinPeriod" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsSharesissuedforAwardsVestedinPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsVestedinPeriodPercentageofTarget" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsVestedinPeriodPercentageofTarget" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofFormsofExecutiveCompensation" name="SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofFormsofExecutiveCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankEqualsto25" name="SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankEqualsto25" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankEqualsto50" name="SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankEqualsto50" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankGreaterthanorEqualsto75" name="SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankGreaterthanorEqualsto75" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankLessthan25" name="SharebasedCompensationArrangementbySharebasedPaymentAwardofEarnedPayoutPercentageBasedonPercentileRankLessthan25" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_SingletenantDataCentersMember" name="SingletenantDataCentersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_StevensInvestorsLLCMember" name="StevensInvestorsLLCMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TaxIncrementalFinancingBondMember" name="TaxIncrementalFinancingBondMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TaxableReitSubsidiaryMember" name="TaxableReitSubsidiaryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TenantandOtherCapitalImprovementsMember" name="TenantandOtherCapitalImprovementsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TermLoanFacilityMember" name="TermLoanFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_ThirdPartyConstructionMember" name="ThirdPartyConstructionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TimebasedProfitInterestUnitsMember" name="TimebasedProfitInterestUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TotalPropertiesNetMember" name="TotalPropertiesNetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TwoThousandEighteenCommonStockAttheMarketProgramMember" name="TwoThousandEighteenCommonStockAttheMarketProgramMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TwoThousandNineteenPIUGrantsMember" name="TwoThousandNineteenPIUGrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_TwoThousandSixteenPSUGrantsMember" name="TwoThousandSixteenPSUGrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ofc_UnconsolidatedJointVentureNetOperatingIncomeAllocabletoParent" name="UnconsolidatedJointVentureNetOperatingIncomeAllocabletoParent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_UnitedStatesGovernmentMember" name="UnitedStatesGovernmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_UnitsByNameAxis" name="UnitsByNameAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_UnitsClassDomain" name="UnitsClassDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_UnvestedPIUsMember" name="UnvestedPIUsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_VariableRateDebtMember" name="VariableRateDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_VehiclesandOfficeEquipmentMember" name="VehiclesandOfficeEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ofc_WholesaleDataCenterMember" name="WholesaleDataCenterMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
