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  <xs:element id="opi_RestrictedCashPeriodIncreaseDecreaseIncludingExchangeRateEffectContinuingOperations" abstract="false" name="RestrictedCashPeriodIncreaseDecreaseIncludingExchangeRateEffectContinuingOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfSecuredNotesDue2031Member" abstract="true" name="IssuanceOfSecuredNotesDue2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_IssuanceOfSecuredNotesDue2029Member" abstract="true" name="IssuanceOfSecuredNotesDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SettlementOfDIPFacilityMember" abstract="true" name="SettlementOfDIPFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_AccrualOfCertainSuccessFee" abstract="false" name="AccrualOfCertainSuccessFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfNewWarrants" abstract="false" name="IssuanceOfNewWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_AccrualOfSettlementFee" abstract="false" name="AccrualOfSettlementFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReinstatementOfAccountsPayableFromLiabilitiesSubjectToCompromise" abstract="false" name="ReinstatementOfAccountsPayableFromLiabilitiesSubjectToCompromise" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_PaymentOfAccruedLenderFeesAndExpenses" abstract="false" name="PaymentOfAccruedLenderFeesAndExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_EquitizationOfDIPFacilityFees" abstract="false" name="EquitizationOfDIPFacilityFees" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_GainOnSettlementOfPostpetitionAccruedInterest" abstract="false" name="GainOnSettlementOfPostpetitionAccruedInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReclassificationOfAccountsPayableAndOtherLiabilitiesForPropertiesHeldForSale" abstract="false" name="ReclassificationOfAccountsPayableAndOtherLiabilitiesForPropertiesHeldForSale" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_PaymentOfAccruedInterestOnCertainPrepetitionDebtFromCashAndCashEquivalents" abstract="false" name="PaymentOfAccruedInterestOnCertainPrepetitionDebtFromCashAndCashEquivalents" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_PaymentOfAccruedInterestOnCertainPrepetitionDebtFromRestrictedCash" abstract="false" name="PaymentOfAccruedInterestOnCertainPrepetitionDebtFromRestrictedCash" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReinstatementOfLiabilitiesSubjectToCompromiseAccountsPayable" abstract="false" name="ReinstatementOfLiabilitiesSubjectToCompromiseAccountsPayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfReorganizedCommonEquityToHoldersOfCertainPrepetitionClaims" abstract="false" name="IssuanceOfReorganizedCommonEquityToHoldersOfCertainPrepetitionClaims" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfReorganizedCommonEquityInConnectionWithTheRightsOffering" abstract="false" name="IssuanceOfReorganizedCommonEquityInConnectionWithTheRightsOffering" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_RecognitionOfSettlementFee" abstract="false" name="RecognitionOfSettlementFee" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfReorganizedCommonEquityInConnectionWithTheRightsOfferingBackstopAgreement" abstract="false" name="IssuanceOfReorganizedCommonEquityInConnectionWithTheRightsOfferingBackstopAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_GainLossOnSettlementOfLiabilitiesSubjectToCompromise" abstract="false" name="GainLossOnSettlementOfLiabilitiesSubjectToCompromise" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfReorganizedCommonEquityInConnectionWithTheSettlementOfDIPFacilityAndDIPFacilityFeeClaims" abstract="false" name="IssuanceOfReorganizedCommonEquityInConnectionWithTheSettlementOfDIPFacilityAndDIPFacilityFeeClaims" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_IssuanceOfReorganizedCommonEquityToRMRInConnectionWithAmendedBusinessManagementAgreement" abstract="false" name="IssuanceOfReorganizedCommonEquityToRMRInConnectionWithAmendedBusinessManagementAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_GainLossOnSettlementOfDIPFacilityClaimsIncludingFeesAndExpenses" abstract="false" name="GainLossOnSettlementOfDIPFacilityClaimsIncludingFeesAndExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_RecognitionOfLenderProfessionalFeesAndExpensesIncludingLenderSuccessFees" abstract="false" name="RecognitionOfLenderProfessionalFeesAndExpensesIncludingLenderSuccessFees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_TotalReorganizationItemsNet" abstract="false" name="TotalReorganizationItemsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_CancelationOfCommonStockAndAdditionalPaidInCapital" abstract="false" name="CancelationOfCommonStockAndAdditionalPaidInCapital" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_NetChangeInCumulativeNetIncome" abstract="false" name="NetChangeInCumulativeNetIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReorganizationGainLossOnSettlementOfLiabilitiesSubjectToCompromise" abstract="false" name="ReorganizationGainLossOnSettlementOfLiabilitiesSubjectToCompromise" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReorganizationFreshStartReportingGainLoss" abstract="false" name="ReorganizationFreshStartReportingGainLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReorganizationGainLossOnExtinguishmentOfDebt" abstract="false" name="ReorganizationGainLossOnExtinguishmentOfDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ReorganizationItemsOther" abstract="false" name="ReorganizationItemsOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ScheduleOfEarningsPerShareBasicAndDilutedTable" abstract="true" name="ScheduleOfEarningsPerShareBasicAndDilutedTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="opi_ScheduleOfEarningsPerShareBasicAndDilutedLineItems" abstract="true" name="ScheduleOfEarningsPerShareBasicAndDilutedLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="opi_JointVentureProperty1Member" abstract="true" name="JointVentureProperty1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_NumberOfOperatingLeaseExecuted" abstract="false" name="NumberOfOperatingLeaseExecuted" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriodAreaOfLeasedProperty" abstract="false" name="OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriodAreaOfLeasedProperty" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
  <xs:element id="opi_OperatingLeasesWeightedAverageLeaseTerm" abstract="false" name="OperatingLeasesWeightedAverageLeaseTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="opi_OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriod" abstract="false" name="OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriodCommittedButUnspentTenantRelatedObligations" abstract="false" name="OperatingLeasesCommittedExpendituresOnLeasesExecutedInPeriodCommittedButUnspentTenantRelatedObligations" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_NumberOfJointVentures" abstract="false" name="NumberOfJointVentures" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_RedwoodCityCAMember" abstract="true" name="RedwoodCityCAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_PhiladelphiaPAMember" abstract="true" name="PhiladelphiaPAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_PittsfordNYMember" abstract="true" name="PittsfordNYMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_IndianapolisINMember" abstract="true" name="IndianapolisINMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_RestonVAMember" abstract="true" name="RestonVAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ColumbiaMDMember" abstract="true" name="ColumbiaMDMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_BaltimoreMDMember" abstract="true" name="BaltimoreMDMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_LakewoodCOMember" abstract="true" name="LakewoodCOMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_RichmondVAMember" abstract="true" name="RichmondVAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_RealEstateAggregateSalesPrice" abstract="false" name="RealEstateAggregateSalesPrice" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_ProsperityMetroPlazaMember" abstract="true" name="ProsperityMetroPlazaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_TenantReimbursementIncome" abstract="false" name="TenantReimbursementIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_RealEstateRevenueNetMember" abstract="true" name="RealEstateRevenueNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_USGovernmentStateGovernmentsAndOtherGovernmentMember" abstract="false" name="USGovernmentStateGovernmentsAndOtherGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_USGovernmentMember" abstract="true" name="USGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_NumberOfStatesInWhichRealEstatePropertiesHeld" abstract="false" name="NumberOfStatesInWhichRealEstatePropertiesHeld" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_SecuredRevolvingCreditFacilityMember" abstract="true" name="SecuredRevolvingCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SecuredTermLoanDue2027Member" abstract="true" name="SecuredTermLoanDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A2650SeniorUnsecuredNotesMember" abstract="true" name="A2650SeniorUnsecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A2.400SeniorUnsecuredNotesMember" abstract="true" name="A2.400SeniorUnsecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A8272MortgageNotesPayableMember" abstract="true" name="A8272MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A8139MortgageNotesPayableMember" abstract="true" name="A8139MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A7671MortgageNotesPayableMember" abstract="true" name="A7671MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A8.375SeniorSecuredNotesPayableDueInDecember2029Member" abstract="true" name="A8.375SeniorSecuredNotesPayableDueInDecember2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A10.000SeniorSecuredNotesPayableDue2031Member" abstract="true" name="A10.000SeniorSecuredNotesPayableDue2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A3.450SeniorUnsecuredNotesMember" abstract="true" name="A3.450SeniorUnsecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A7210MortgageNotesPayableMember" abstract="true" name="A7210MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A7305MortgageNotesPayableMember" abstract="true" name="A7305MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A7717MortgageNotesPayableMember" abstract="true" name="A7717MortgageNotesPayableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A6.375SeniorUnsecuredNotesMember" abstract="true" name="A6.375SeniorUnsecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_A10.000SeniorSecuredNotesPayableDueInSeptember2029Member" abstract="true" name="A10.000SeniorSecuredNotesPayableDueInSeptember2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_DebtInstrumentPeriodicPaymentAxis" abstract="true" name="DebtInstrumentPeriodicPaymentAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="opi_DebtInstrumentPeriodicPaymentDomain" abstract="true" name="DebtInstrumentPeriodicPaymentDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_DebtInstrumentPeriodThreeMember" abstract="true" name="DebtInstrumentPeriodThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_DebtInstrumentPeriodFourMember" abstract="true" name="DebtInstrumentPeriodFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_LongTermDebtTermsAxis" abstract="true" name="LongTermDebtTermsAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="opi_LongTermDebtTermsDomain" abstract="true" name="LongTermDebtTermsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_TrancheASubsequentDrawMember" abstract="true" name="TrancheASubsequentDrawMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_TrancheBMember" abstract="true" name="TrancheBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_AggregateGrossBookValueOfRealEstateAssetsCollateralized" abstract="false" name="AggregateGrossBookValueOfRealEstateAssetsCollateralized" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_DebtInstrumentCovenantDistributionRateMaximum" abstract="false" name="DebtInstrumentCovenantDistributionRateMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="opi_WeightedAverageAnnualInterestRate" abstract="false" name="WeightedAverageAnnualInterestRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_NumberOfBorrowersWithWaiverAgreements" abstract="false" name="NumberOfBorrowersWithWaiverAgreements" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_DebtInstrumentAmountAvailableToBeDrawn" abstract="false" name="DebtInstrumentAmountAvailableToBeDrawn" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_DebtInstrumentUpfrontFeePercentageCashCommitment" abstract="false" name="DebtInstrumentUpfrontFeePercentageCashCommitment" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_DebtInstrumentUpfrontFeePercentageReorganizedCommonEquityCommitment" abstract="false" name="DebtInstrumentUpfrontFeePercentageReorganizedCommonEquityCommitment" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_DebtInstrumentCapitalCommitmentFeePercentage" abstract="false" name="DebtInstrumentCapitalCommitmentFeePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_DebtInstrumentExitFeePercentage" abstract="false" name="DebtInstrumentExitFeePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_A10.000SeniorSecuredNotesMember" abstract="true" name="A10.000SeniorSecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SeniorNotesAndMortgagesMember" abstract="true" name="SeniorNotesAndMortgagesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_NumberOfEmployees" abstract="false" name="NumberOfEmployees" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_NumberOfAgreements" abstract="false" name="NumberOfAgreements" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_ManagementFeeTerm" abstract="false" name="ManagementFeeTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="opi_AnnualManagementFee" abstract="false" name="AnnualManagementFee" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_AnnualManagementFeePeriodForFee" abstract="false" name="AnnualManagementFeePeriodForFee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="opi_RelatedPartyTransactionPropertyManagementFeesAsPercentageOfGrossCollectedRents" abstract="false" name="RelatedPartyTransactionPropertyManagementFeesAsPercentageOfGrossCollectedRents" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionConstructionSupervisionFeesAsPercentageOfConstructionCosts" abstract="false" name="RelatedPartyTransactionConstructionSupervisionFeesAsPercentageOfConstructionCosts" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionPercentageOfSharesIssuedBasedOnOutstandingCommonShares" abstract="false" name="RelatedPartyTransactionPercentageOfSharesIssuedBasedOnOutstandingCommonShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionAdditionalPotentialPercentageOfSharesIssuedBasedOnOutstandingCommonShares" abstract="false" name="RelatedPartyTransactionAdditionalPotentialPercentageOfSharesIssuedBasedOnOutstandingCommonShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_PropertyManagementAgreementMember" abstract="true" name="PropertyManagementAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_PropertyManagementAgreementPropertyManagementFeesMember" abstract="true" name="PropertyManagementAgreementPropertyManagementFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_PropertyManagementAgreementConstructionSupervisionFeesMember" abstract="true" name="PropertyManagementAgreementConstructionSupervisionFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ExpenseReimbursementMember" abstract="true" name="ExpenseReimbursementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ExpenseReimbursementPropertyLevelExpensesMember" abstract="true" name="ExpenseReimbursementPropertyLevelExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ExpenseReimbursementOtherReimbursedExpensesMember" abstract="true" name="ExpenseReimbursementOtherReimbursedExpensesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_RelatedPartyTransactionAmortizationOfLiability" abstract="false" name="RelatedPartyTransactionAmortizationOfLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_RelatedPartyReimbursementExpense" abstract="false" name="RelatedPartyReimbursementExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_SonestaInternationalHotelsCorporationMember" abstract="true" name="SonestaInternationalHotelsCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ManagementAgreementPriorityReturnMember" abstract="true" name="ManagementAgreementPriorityReturnMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SonestaManagementAgreementPeriodOneMember" abstract="true" name="SonestaManagementAgreementPeriodOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SonestaManagementAgreementPeriodTwoMember" abstract="true" name="SonestaManagementAgreementPeriodTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_SonestaManagementAgreementPeriodThreeMember" abstract="true" name="SonestaManagementAgreementPeriodThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_ManagementBrandPromotionAndLoyaltyFeesMember" abstract="true" name="ManagementBrandPromotionAndLoyaltyFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_WorkingCapitalMember" abstract="true" name="WorkingCapitalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_AssetManagementAmortizationMember" abstract="true" name="AssetManagementAmortizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="opi_NumberOfAgreementsWithRmrLlc" abstract="false" name="NumberOfAgreementsWithRmrLlc" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_RelatedPartyTransactionNumberOfRenewalOptions" abstract="false" name="RelatedPartyTransactionNumberOfRenewalOptions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="opi_RelatedPartyTransactionRenewalTerm" abstract="false" name="RelatedPartyTransactionRenewalTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="opi_RelatedPartyTransactionPriorityReturnIncreasePercentOfCapitalExpenditures" abstract="false" name="RelatedPartyTransactionPriorityReturnIncreasePercentOfCapitalExpenditures" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionMaximumPriorityReturnOfPriorYearPriorityReturn" abstract="false" name="RelatedPartyTransactionMaximumPriorityReturnOfPriorYearPriorityReturn" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionRequiredEscrowDepositPercentOfGrossRevenues" abstract="false" name="RelatedPartyTransactionRequiredEscrowDepositPercentOfGrossRevenues" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionBaseManageFeePercentOfGrossRevenues" abstract="false" name="RelatedPartyTransactionBaseManageFeePercentOfGrossRevenues" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionIncentiveFeePercentOfNetOperatingProfit" abstract="false" name="RelatedPartyTransactionIncentiveFeePercentOfNetOperatingProfit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionBrandPromotionFeePercentOfGrossRevenues" abstract="false" name="RelatedPartyTransactionBrandPromotionFeePercentOfGrossRevenues" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionLoyaltyFeePercentOfRoomRevenues" abstract="false" name="RelatedPartyTransactionLoyaltyFeePercentOfRoomRevenues" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_RelatedPartyTransactionLoyaltyFeePercentOfQualifiedRoomRevenues" abstract="false" name="RelatedPartyTransactionLoyaltyFeePercentOfQualifiedRoomRevenues" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="opi_HotelOperatingRevenues" abstract="false" name="HotelOperatingRevenues" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_HotelReturns" abstract="false" name="HotelReturns" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_FFEEscrowDeposits" abstract="false" name="FFEEscrowDeposits" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="opi_LoyaltyFeeExpense" abstract="false" name="LoyaltyFeeExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
