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  <xs:element id="fivn_DebtInstrumentRedemptionMinimumAggregatePrincipalAmountOutstandingRequiredForRedemption" abstract="false" name="DebtInstrumentRedemptionMinimumAggregatePrincipalAmountOutstandingRequiredForRedemption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleCappedCallTransactionsCapPrice" abstract="false" name="DebtInstrumentConvertibleCappedCallTransactionsCapPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="fivn_DebtInstrumentCappedCallTransactionsSharesCoverage" abstract="false" name="DebtInstrumentCappedCallTransactionsSharesCoverage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fivn_EquityIncentivePlan2014Member" abstract="true" name="EquityIncentivePlan2014Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_PerformanceBasedAndMarketBasedRestrictedStockUnitsPRSUsMember" abstract="true" name="PerformanceBasedAndMarketBasedRestrictedStockUnitsPRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_StockholdersEquityCapitalStructureTable" abstract="true" name="StockholdersEquityCapitalStructureTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_MarketBasedPRSUsMember" abstract="true" name="MarketBasedPRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_PerformanceBasedRestrictedStockUnitsPRSUsMember" abstract="true" name="PerformanceBasedRestrictedStockUnitsPRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_EquityInstrumentConditionAxis" abstract="true" name="EquityInstrumentConditionAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_EquityInstrumentConditionDomain" abstract="true" name="EquityInstrumentConditionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_ExecutiveEmploymentTerminatesDueToDeathByEndOf2024Member" abstract="true" name="ExecutiveEmploymentTerminatesDueToDeathByEndOf2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_ExecutiveEmploymentTerminatesDueToDisabilityByEndOf2024Member" abstract="true" name="ExecutiveEmploymentTerminatesDueToDisabilityByEndOf2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_ShareholderForPerformanceAnyPeriodIsNegativeMember" abstract="true" name="ShareholderForPerformanceAnyPeriodIsNegativeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_StockholdersEquityCapitalStructureLineItems" abstract="true" name="StockholdersEquityCapitalStructureLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThenOptionsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThenOptionsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfTargetedAward" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfTargetedAward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfPerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfPerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfTotalShareholderReturn" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfTotalShareholderReturn" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfRelativeTotalShareholderReturnRanking" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfRelativeTotalShareholderReturnRanking" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="fivn_AcqueonMember" abstract="true" name="AcqueonMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_BusinessCombinationRecognizedLiabilityAssumedDomesticNetDeferredTaxLiability" abstract="false" name="BusinessCombinationRecognizedLiabilityAssumedDomesticNetDeferredTaxLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_HostingandTelecommunicationsAgreementMember" abstract="true" name="HostingandTelecommunicationsAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_PurchaseCommitmentCloudServicesAgreementMember" abstract="true" name="PurchaseCommitmentCloudServicesAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_OtherCommitmentFutureMinimumPaymentsDuePeriod" abstract="false" name="OtherCommitmentFutureMinimumPaymentsDuePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_CommercialCommitmentsExpiring" abstract="false" name="CommercialCommitmentsExpiring" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_CommercialCommitmentToBePaidRemainderOfTheYear" abstract="false" name="CommercialCommitmentToBePaidRemainderOfTheYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_CommercialCommitmentToBePaidYearOne" abstract="false" name="CommercialCommitmentToBePaidYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_CommitmentAndContingenciesCommercialCommitmentReduction" abstract="false" name="CommitmentAndContingenciesCommercialCommitmentReduction" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_CostOfRevenueAdjusted" abstract="false" name="CostOfRevenueAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ResearchAndDevelopmentExpenseAdjusted" abstract="false" name="ResearchAndDevelopmentExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AdjustedSalesAndMarketingExpense" abstract="false" name="AdjustedSalesAndMarketingExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_GeneralAndAdministrativeExpenseAdjusted" abstract="false" name="GeneralAndAdministrativeExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseOptionToTerminateNotice" abstract="false" name="LesseeOperatingLeaseOptionToTerminateNotice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_FinanceLeaseLiabilityAcquiredCurrent" abstract="false" name="FinanceLeaseLiabilityAcquiredCurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_FinanceLeaseLiabilityAcquiredNonCurrent" abstract="false" name="FinanceLeaseLiabilityAcquiredNonCurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_RightOfUseAssetsObtainedInExchangeForLeaseObligationsAbstract" abstract="true" name="RightOfUseAssetsObtainedInExchangeForLeaseObligationsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="fivn_FixedAssetsExcludingNewFinanceLeaseMember" abstract="true" name="FixedAssetsExcludingNewFinanceLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssetsAcquired" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedTangibleAssetsAcquired" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAcquiredIncludingGoodwill" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAcquiredIncludingGoodwill" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_A2024PlanMember" abstract="true" name="A2024PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_A2025PlanMember" abstract="true" name="A2025PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_AndrewDignanMember" abstract="true" name="AndrewDignanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_BryanLeeMember" abstract="true" name="BryanLeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
