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  <xs:element id="tls_ClassesOfMembershipUnits" abstract="false" name="ClassesOfMembershipUnits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_TelosCorporationMember" abstract="true" name="TelosCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_PreferredStockConversionPrice" abstract="false" name="PreferredStockConversionPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="tls_InventoryValuationReservesAdditionsChargedToCostsAndExpenses" abstract="false" name="InventoryValuationReservesAdditionsChargedToCostsAndExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" 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_ProductsAndServicesMember" abstract="true" name="ProductsAndServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_AdditionalPercentageOfOwnershipAcquired" abstract="false" name="AdditionalPercentageOfOwnershipAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tls_NonTradeReceivableCreditLossExpenseReversal" abstract="false" name="NonTradeReceivableCreditLossExpenseReversal" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_RevenueRelatedToStubPeriodOfAContractMember" abstract="true" name="RevenueRelatedToStubPeriodOfAContractMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_ServiceBasedRSUAwardsMember" abstract="true" name="ServiceBasedRSUAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_FederalGovernmentMember" abstract="true" name="FederalGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveSharesInConditionTwo" abstract="false" name="ERPSConversionAmountIntoRightToReceiveSharesInConditionTwo" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_WeightedAverageOfConsecutiveTradingDaysRequiredForSharesEqualToTargetPrice" abstract="false" name="WeightedAverageOfConsecutiveTradingDaysRequiredForSharesEqualToTargetPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_CivilianMember" abstract="true" name="CivilianMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_DeferredTaxAssetsValuationAllowanceRecoveries" abstract="false" name="DeferredTaxAssetsValuationAllowanceRecoveries" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_DeferredTaxAssetsTaxDeductibleGoodwill" abstract="false" name="DeferredTaxAssetsTaxDeductibleGoodwill" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_MaximumLimitOfReceivablesSold" abstract="false" name="MaximumLimitOfReceivablesSold" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_USDepartmentOfDefenseMember" abstract="true" name="USDepartmentOfDefenseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_CostPlusFixedFeeMember" abstract="true" name="CostPlusFixedFeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_ERPSConversionAmountIntoRightToReceiveCashInConditionOne" abstract="false" name="ERPSConversionAmountIntoRightToReceiveCashInConditionOne" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tls_OverheadCostPoolsStockCompensationMember" abstract="true" name="OverheadCostPoolsStockCompensationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_ClassMembershipUnitMember" abstract="true" name="ClassMembershipUnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_DeferredTaxLiabilitiesUnbilledAccountsReceivableDeferredForTaxPurposes" abstract="false" name="DeferredTaxLiabilitiesUnbilledAccountsReceivableDeferredForTaxPurposes" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_NumberOfQuarterlyMaturityDateExtensions" abstract="false" name="NumberOfQuarterlyMaturityDateExtensions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_PercentageOfWarrantsIssuedOfCommonEquityInterests" abstract="false" name="PercentageOfWarrantsIssuedOfCommonEquityInterests" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tls_SecuritySolutionsSegmentMember" abstract="true" name="SecuritySolutionsSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_SingleIndividualStockCompensationMember" abstract="true" name="SingleIndividualStockCompensationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_AnnualRentIncreasePercentage" abstract="false" name="AnnualRentIncreasePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tls_GainOnRedemptionOfPublicPreferredStock" abstract="false" name="GainOnRedemptionOfPublicPreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_DeferredTaxAssetsInterestLimiitation" abstract="false" name="DeferredTaxAssetsInterestLimiitation" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_ScheduleOfObsolescentInventoryTableTextBlock" abstract="false" name="ScheduleOfObsolescentInventoryTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="tls_IncreaseInCapitalLeasedProperty" abstract="false" name="IncreaseInCapitalLeasedProperty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_DistributionsToNonControllingInterest" abstract="false" name="DistributionsToNonControllingInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_EffectiveIncomeTaxRateReconciliationDeductionsGainOnRedemptionOfPreferredStock" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeductionsGainOnRedemptionOfPreferredStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_ReceivablesSoldUnderFactoringAgreement" abstract="false" name="ReceivablesSoldUnderFactoringAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_LeaseWeightedAverageDiscountRateAbstract" abstract="true" name="LeaseWeightedAverageDiscountRateAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tls_TermOfLease" abstract="false" name="TermOfLease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_IncreaseInCapitalLeaseObligations" abstract="false" name="IncreaseInCapitalLeaseObligations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingThresholdTradingDays" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingThresholdTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_ExpenseRelatedToASoftwareProjectMember" abstract="true" name="ExpenseRelatedToASoftwareProjectMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_EffectiveIncomeTaxRateReconciliationCapitalizationOfIPOTransactionCosts" abstract="false" name="EffectiveIncomeTaxRateReconciliationCapitalizationOfIPOTransactionCosts" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tls_CreditAgreementMember" abstract="true" name="CreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tls_NumberOfConsecutiveQuarters" abstract="false" name="NumberOfConsecutiveQuarters" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_EffectiveIncomeTaxRateReconciliationSection162MLimitation" abstract="false" name="EffectiveIncomeTaxRateReconciliationSection162MLimitation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tls_NetBookValueOfCapitalAsset" abstract="false" name="NetBookValueOfCapitalAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_RevenueTimingOfTransferOfGoodsOrServiceMember" abstract="true" name="RevenueTimingOfTransferOfGoodsOrServiceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_PercentageRestrictedStockVestedOnDateOfGrant" abstract="false" name="PercentageRestrictedStockVestedOnDateOfGrant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_NumberOfMembersInBoardOfDirector" abstract="false" name="NumberOfMembersInBoardOfDirector" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tls_WarrantRepurchasedDuringPeriodShares" abstract="false" name="WarrantRepurchasedDuringPeriodShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_DebtIssuanceCostsAndPrepaymentOfInterestOnSeniorTermLoan" abstract="false" name="DebtIssuanceCostsAndPrepaymentOfInterestOnSeniorTermLoan" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tls_ChangesInNonControllingInterestTableTextBlock" abstract="false" name="ChangesInNonControllingInterestTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="tls_NumberOfDirectorsEntitledToAppoint" abstract="false" name="NumberOfDirectorsEntitledToAppoint" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tls_NumberOfSharesHeldByRelatedParty" abstract="false" name="NumberOfSharesHeldByRelatedParty" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tls_Two016OmnibusLongTermIncentivePlanMember" abstract="true" name="Two016OmnibusLongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
