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      <link:roleType id="StockBasedCompensationStockBasedCompensationExpenseIncurredDetails" roleURI="http://telos.com/role/StockBasedCompensationStockBasedCompensationExpenseIncurredDetails">
        <link:definition>2441426 - Disclosure - Stock-Based Compensation - Stock-Based Compensation Expense Incurred (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationServiceBasedRSUAwardsDetails" roleURI="http://telos.com/role/StockBasedCompensationServiceBasedRSUAwardsDetails">
        <link:definition>2442427 - Disclosure - Stock-Based Compensation - Service-Based RSU Awards (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="StockBasedCompensationPerformanceBasedRSUAwardsDetails" roleURI="http://telos.com/role/StockBasedCompensationPerformanceBasedRSUAwardsDetails">
        <link:definition>2443428 - Disclosure - Stock-Based Compensation - Performance-Based RSU Awards (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xs:appinfo>
  </xs:annotation>
  <xs:element id="tls_AmendmentFeeAndOutOfPocketCostsAndExpenses" abstract="false" name="AmendmentFeeAndOutOfPocketCostsAndExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_WorkingCapital" abstract="false" name="WorkingCapital" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate" abstract="false" name="UnrecognizedTaxBenefitsThatWouldNotImpactEffectiveTaxRate" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_WarrantsRepurchasedDuringPeriodValue" abstract="false" name="WarrantsRepurchasedDuringPeriodValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_TelosIdMember" abstract="true" name="TelosIdMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_PublicPreferredStockAccretionOfRedemptionDiscount" abstract="false" name="PublicPreferredStockAccretionOfRedemptionDiscount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_FinanceLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="FinanceLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_DebtInstrumentTransactionCosts" abstract="false" name="DebtInstrumentTransactionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveCashInConditionTwo" abstract="false" name="ERPSConversionAmountIntoRightToReceiveCashInConditionTwo" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_ExchangeableRedeemablePreferredStockMember" abstract="true" name="ExchangeableRedeemablePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_ImpactOfStockIssuanceToAdditionalPaidInCapitalFromBusinessCombination" abstract="false" name="ImpactOfStockIssuanceToAdditionalPaidInCapitalFromBusinessCombination" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_ClassMembershipUnitMember" abstract="true" name="ClassMembershipUnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_NumberOfConsecutiveTradingDaysRequiredForSharesToVest" abstract="false" name="NumberOfConsecutiveTradingDaysRequiredForSharesToVest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tls_ClassBMembershipUnitMember" abstract="true" name="ClassBMembershipUnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_NumberOfQuarterlyMaturityDateExtensions" abstract="false" name="NumberOfQuarterlyMaturityDateExtensions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_PreferredStockConversionPrice" abstract="false" name="PreferredStockConversionPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="tls_NetBookValueOfAssetsContributed" abstract="false" name="NetBookValueOfAssetsContributed" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_TelosIDTeloworksAndTelosAPACMember" abstract="true" name="TelosIDTeloworksAndTelosAPACMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_NumberOfDirectorsEntitledToAppoint" abstract="false" name="NumberOfDirectorsEntitledToAppoint" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_PorterMember" abstract="true" name="PorterMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_FinanceLeaseCostsAbstract" abstract="true" name="FinanceLeaseCostsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveCashInConditionOne" abstract="false" name="ERPSConversionAmountIntoRightToReceiveCashInConditionOne" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveSharesInConditionTwo" abstract="false" name="ERPSConversionAmountIntoRightToReceiveSharesInConditionTwo" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_SecondaryPublicOfferingMember" abstract="true" name="SecondaryPublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_CreditAgreementMember" abstract="true" name="CreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_PercentageOfRedeemablePreferredStockHeldByRelatedPartyAfterRedemption" abstract="false" name="PercentageOfRedeemablePreferredStockHeldByRelatedPartyAfterRedemption" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_FederalGovernmentMember" abstract="true" name="FederalGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_WeightedAverageOfConsecutiveTradingDaysRequiredForSharesEqualToTargetPrice" abstract="false" name="WeightedAverageOfConsecutiveTradingDaysRequiredForSharesEqualToTargetPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tls_WarrantRepurchasedDuringPeriodShares" abstract="false" name="WarrantRepurchasedDuringPeriodShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_PercentageOfWarrantsIssuedOfCommonEquityInterests" abstract="false" name="PercentageOfWarrantsIssuedOfCommonEquityInterests" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_TwelvePercentCumulativeExchangeableRedeemablePreferredStockMember" abstract="true" name="TwelvePercentCumulativeExchangeableRedeemablePreferredStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_AdditionalPercentageOfOwnershipAcquired" abstract="false" name="AdditionalPercentageOfOwnershipAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_NumberOfMembersInBoardOfDirector" abstract="false" name="NumberOfMembersInBoardOfDirector" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveSharesInConditionOne" abstract="false" name="ERPSConversionAmountIntoRightToReceiveSharesInConditionOne" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_DebtInstrumentAgentFeeAmount" abstract="false" name="DebtInstrumentAgentFeeAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_SaleOfStockNumberOfSharesIssuedByCertainExistingShareholders" abstract="false" name="SaleOfStockNumberOfSharesIssuedByCertainExistingShareholders" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_CashConsiderationReceivedOnSaleOfMembershipInterest" abstract="false" name="CashConsiderationReceivedOnSaleOfMembershipInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_NumberOfRedeemablePreferredStockRedeemed" abstract="false" name="NumberOfRedeemablePreferredStockRedeemed" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_HamotMember" abstract="true" name="HamotMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_PrepaymentPricePercentageTwo" abstract="false" name="PrepaymentPricePercentageTwo" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_NumberOfConsecutiveQuarters" abstract="false" name="NumberOfConsecutiveQuarters" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_EnlightenmentCapitalSolutionsFundIILPMember" abstract="true" name="EnlightenmentCapitalSolutionsFundIILPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_PrepaymentPricePercentageOne" abstract="false" name="PrepaymentPricePercentageOne" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_StockIssuedDuringPeriodValueFractionalShares" abstract="false" name="StockIssuedDuringPeriodValueFractionalShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_CashPaidDuringPeriodForAbstract" abstract="true" name="CashPaidDuringPeriodForAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tls_NumberOfSharesHeldByChiefExecutiveOfficer" abstract="false" name="NumberOfSharesHeldByChiefExecutiveOfficer" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_AmountOfIncreaseDecreaseInQuarterlyExitFeePayable" abstract="false" name="AmountOfIncreaseDecreaseInQuarterlyExitFeePayable" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_NumberOfAllocatedConsecutiveTradingDaysRequiredForSharesToVest" abstract="false" name="NumberOfAllocatedConsecutiveTradingDaysRequiredForSharesToVest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tls_AmountOfIncreaseDecreaseInExitFeePayable" abstract="false" name="AmountOfIncreaseDecreaseInExitFeePayable" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_StateLocalAndCommercialMember" abstract="true" name="StateLocalAndCommercialMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_RedeemablePreferredStockTextBlock" abstract="false" name="RedeemablePreferredStockTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="tls_PercentageOfMembershipInterestSoldToInvestor" abstract="false" name="PercentageOfMembershipInterestSoldToInvestor" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_ServiceBasedRSUAwardsMember" abstract="true" name="ServiceBasedRSUAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_PercentageOfProfitAndLossAllocated" abstract="false" name="PercentageOfProfitAndLossAllocated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="tls_WarrantsAcquiredAverageCostPerShare" abstract="false" name="WarrantsAcquiredAverageCostPerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="tls_NumberOfSharesHeldByRelatedParty" abstract="false" name="NumberOfSharesHeldByRelatedParty" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_NumberOfEmployeesHired" abstract="false" name="NumberOfEmployeesHired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_PreferredStockRedemptionCosts" abstract="false" name="PreferredStockRedemptionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_Two016OmnibusLongTermIncentivePlanMember" abstract="true" name="Two016OmnibusLongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_EmmettWoodMember" abstract="true" name="EmmettWoodMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tls_DividendsPreferredStockAsInterestExpense" abstract="false" name="DividendsPreferredStockAsInterestExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_CostPlusFixedFeeMember" abstract="true" name="CostPlusFixedFeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
</xs:schema>
