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  <xsd:element id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreaseShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreaseShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForIssuance" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedInPeriodTotalFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValueAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfVestedOptions" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfVestedOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="qlys_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeVestedOptionsWeightedAverageExercisePrice" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeVestedOptionsWeightedAverageExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="qlys_ShareholdersEquityCommonStockAbstract" name="ShareholdersEquityCommonStockAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="qlys_ShareholdersEquityConvertiblePreferredStockAndPreferredStockAbstract" name="ShareholdersEquityConvertiblePreferredStockAndPreferredStockAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_SharesSoldByExistingStockholdersDuringInitialPublicOffering" name="SharesSoldByExistingStockholdersDuringInitialPublicOffering" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_SharesSoldInInitialPublicOfferingIncludingExistingShares" name="SharesSoldInInitialPublicOfferingIncludingExistingShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_SharesSoldInInitialPublicOfferingIncludingExistingSharesPricePerShare" name="SharesSoldInInitialPublicOfferingIncludingExistingSharesPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="qlys_StockholdersEquityLineItems" name="StockholdersEquityLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="qlys_StockholdersEquityTable" name="StockholdersEquityTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="qlys_TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" name="TemporaryEquityStockIssuedDuringPeriodValueConversionOfConvertibleSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
</xsd:schema>
