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  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfRelativeTotalShareholderReturnRanking" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentOfRelativeTotalShareholderReturnRanking" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="fivn_OneClientMember" abstract="true" name="OneClientMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfPerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfPerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="fivn_EquityInstrumentConditionAxis" abstract="true" name="EquityInstrumentConditionAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_MarketableSecuritiesDueYearTwoCostBasis" abstract="false" name="MarketableSecuritiesDueYearTwoCostBasis" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_MarketableSecuritiesDueYearTwoFairValue" abstract="false" name="MarketableSecuritiesDueYearTwoFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_StateTaxLiabilitiesNoncurrent" abstract="false" name="StateTaxLiabilitiesNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_PaymentsForCappedCallTransactionsFinancingActivities" abstract="false" name="PaymentsForCappedCallTransactionsFinancingActivities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_AmortizationOfDeferredContractAcquisitionCosts" abstract="false" name="AmortizationOfDeferredContractAcquisitionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_EquityIncentivePlan2014Member" abstract="true" name="EquityIncentivePlan2014Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleTradingDaysPrecedingRedemptionNotice" abstract="false" name="DebtInstrumentConvertibleTradingDaysPrecedingRedemptionNotice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fivn_EquityInstrumentConditionDomain" abstract="true" name="EquityInstrumentConditionDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="fivn_NumberOfBusinessOpportunities" abstract="false" name="NumberOfBusinessOpportunities" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_PerformanceBasedRestrictedStockUnitsPRSUsMember" abstract="true" name="PerformanceBasedRestrictedStockUnitsPRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="fivn_InvestmentsAndFairValueMeasurementsTextBlock" abstract="false" name="InvestmentsAndFairValueMeasurementsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="fivn_USGovernmentSponsoredEnterprisesDebtSecuritiesAndAgencySecuritiesMember" abstract="true" name="USGovernmentSponsoredEnterprisesDebtSecuritiesAndAgencySecuritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_DebtInstrumentConvertibleTermAxis" abstract="true" name="DebtInstrumentConvertibleTermAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="fivn_CashConsiderationToRepurchaseNote" abstract="false" name="CashConsiderationToRepurchaseNote" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodValueStockOptionsandWarrantsExercised" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_ContractwithCustomerAssetLiabilityNet" abstract="false" name="ContractwithCustomerAssetLiabilityNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" 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-types1:perShareItemType"/>
  <xs:element id="fivn_ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" abstract="false" name="ScheduleOfBalanceSheetInformationRelatedToLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="fivn_PanosKozanianMember" abstract="true" name="PanosKozanianMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_MarketableSecuritiesDueWithinOneYearCostBasis" abstract="false" name="MarketableSecuritiesDueWithinOneYearCostBasis" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_BarryZwarensteinMember" abstract="true" name="BarryZwarensteinMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="fivn_StockIssuedDuringPeriodSharesStockOptionsandWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodSharesStockOptionsandWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="fivn_ProceedsFromPartialTerminationOfCappedCallsAssociatedWithConvertibleSeniorNotes" abstract="false" name="ProceedsFromPartialTerminationOfCappedCallsAssociatedWithConvertibleSeniorNotes" 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_PayoutAtThe25thTSRPercentileMember" abstract="true" name="PayoutAtThe25thTSRPercentileMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="fivn_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfInstallments" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfInstallments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="fivn_IncreaseDecreaseinCapitalizedContractCost" abstract="false" name="IncreaseDecreaseinCapitalizedContractCost" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="fivn_MarketableSecuritiesDueWithinOneYearFairValue" abstract="false" name="MarketableSecuritiesDueWithinOneYearFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
