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  <xsd:element abstract="true" id="qlys_The2012EquityIncentivePlanMember" name="The2012EquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_TimeBasedSharedBasedCompensationMember" name="TimeBasedSharedBasedCompensationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-fair-value-assumptions-stock-options-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-fair-value-assumptions-stock-options-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-reserved-shares-of-common-stock-for-future-issuance-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-reserved-shares-of-common-stock-for-future-issuance-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-sharebased-compensation-and-stock-options-activity-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-sharebased-compensation-and-stock-options-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-sharebased-compensation-restricted-stock-and-restricted-stock-units-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-sharebased-compensation-restricted-stock-and-restricted-stock-units-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-summarizes-the-outstanding-and-vested-stock-options-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-summarizes-the-outstanding-and-vested-stock-options-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-summary-of-stockbased-compensation-expense-details" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-summary-of-stockbased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-10-stockholders-equity-and-stockbased-compensation-tables" name="statement-statement-note-10-stockholders-equity-and-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-schedule-of-components-of-income-tax-expense-benefit-details" name="statement-statement-note-12-income-taxes-schedule-of-components-of-income-tax-expense-benefit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-schedule-of-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-12-income-taxes-schedule-of-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-schedule-of-effective-income-tax-rate-reconciliation-details" name="statement-statement-note-12-income-taxes-schedule-of-effective-income-tax-rate-reconciliation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-schedule-of-income-before-income-tax-domestic-and-foreign-details" name="statement-statement-note-12-income-taxes-schedule-of-income-before-income-tax-domestic-and-foreign-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-schedule-of-unrecognized-tax-benefits-roll-forward-details" name="statement-statement-note-12-income-taxes-schedule-of-unrecognized-tax-benefits-roll-forward-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-12-income-taxes-tables" name="statement-statement-note-12-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-13-segment-information-and-information-about-geographic-area-revenue-and-property-and-equipment-net-by-geographic-area-details" name="statement-statement-note-13-segment-information-and-information-about-geographic-area-revenue-and-property-and-equipment-net-by-geographic-area-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-13-segment-information-and-information-about-geographic-area-tables" name="statement-statement-note-13-segment-information-and-information-about-geographic-area-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-14-net-income-per-share-antidilutive-net-income-per-share-details" name="statement-statement-note-14-net-income-per-share-antidilutive-net-income-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-14-net-income-per-share-basic-and-diluted-net-income-per-share-details" name="statement-statement-note-14-net-income-per-share-basic-and-diluted-net-income-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-14-net-income-per-share-tables" name="statement-statement-note-14-net-income-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-15-selected-quarterly-financial-information-unaudited-schedule-of-quarterly-financial-information-details" name="statement-statement-note-15-selected-quarterly-financial-information-unaudited-schedule-of-quarterly-financial-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-15-selected-quarterly-financial-information-unaudited-tables" name="statement-statement-note-15-selected-quarterly-financial-information-unaudited-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-amounts-recognized-in-statement-of-operations-details" name="statement-statement-note-2-fair-value-of-financial-instruments-amounts-recognized-in-statement-of-operations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-cash-and-cash-equivalents-details" name="statement-statement-note-2-fair-value-of-financial-instruments-cash-and-cash-equivalents-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-fair-value-hierarchy-details" name="statement-statement-note-2-fair-value-of-financial-instruments-fair-value-hierarchy-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-summary-of-derivative-financial-instruments-details" name="statement-statement-note-2-fair-value-of-financial-instruments-summary-of-derivative-financial-instruments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-summary-of-the-fair-value-of-marketable-securities-details" name="statement-statement-note-2-fair-value-of-financial-instruments-summary-of-the-fair-value-of-marketable-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-2-fair-value-of-financial-instruments-tables" name="statement-statement-note-2-fair-value-of-financial-instruments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-3-accumulated-other-comprehensive-income-accumulated-other-comprehensive-income-loss-details" name="statement-statement-note-3-accumulated-other-comprehensive-income-accumulated-other-comprehensive-income-loss-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-3-accumulated-other-comprehensive-income-amounts-reclassified-from-aoci-details" name="statement-statement-note-3-accumulated-other-comprehensive-income-amounts-reclassified-from-aoci-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-3-accumulated-other-comprehensive-income-tables" name="statement-statement-note-3-accumulated-other-comprehensive-income-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-4-property-and-equipment-net-property-and-equipment-net-details" name="statement-statement-note-4-property-and-equipment-net-property-and-equipment-net-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-4-property-and-equipment-net-tables" name="statement-statement-note-4-property-and-equipment-net-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-5-revenue-from-contracts-with-customers-capitalized-cost-to-obtain-contracts-current-and-noncurrent-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-capitalized-cost-to-obtain-contracts-current-and-noncurrent-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-5-revenue-from-contracts-with-customers-expected-revenue-from-all-remaining-performance-obligations-2-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-expected-revenue-from-all-remaining-performance-obligations-2-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-5-revenue-from-contracts-with-customers-expected-revenue-from-all-remaining-performance-obligations-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-expected-revenue-from-all-remaining-performance-obligations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-5-revenue-from-contracts-with-customers-revenue-by-sales-channel-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-revenue-by-sales-channel-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-5-revenue-from-contracts-with-customers-tables" name="statement-statement-note-5-revenue-from-contracts-with-customers-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-6-acquisitions-changes-in-carrying-amount-of-goodwill-details" name="statement-statement-note-6-acquisitions-changes-in-carrying-amount-of-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-6-acquisitions-estimated-fair-values-of-the-acquired-assets-details" name="statement-statement-note-6-acquisitions-estimated-fair-values-of-the-acquired-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-6-acquisitions-tables" name="statement-statement-note-6-acquisitions-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-7-intangible-assets-net-carrying-value-of-intangible-assets-details" name="statement-statement-note-7-intangible-assets-net-carrying-value-of-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-7-intangible-assets-net-expected-amortization-expense-in-future-periods-details" name="statement-statement-note-7-intangible-assets-net-expected-amortization-expense-in-future-periods-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-7-intangible-assets-net-tables" name="statement-statement-note-7-intangible-assets-net-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-8-leases-leaserelated-assets-and-liabilities-details" name="statement-statement-note-8-leases-leaserelated-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-8-leases-minimum-annual-lease-payments-details" name="statement-statement-note-8-leases-minimum-annual-lease-payments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-8-leases-supplemental-cash-flow-information-details" name="statement-statement-note-8-leases-supplemental-cash-flow-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-8-leases-tables" name="statement-statement-note-8-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-8-leases-weighted-average-remaining-lease-term-and-weighted-average-discount-rate-details" name="statement-statement-note-8-leases-weighted-average-remaining-lease-term-and-weighted-average-discount-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-9-commitment-and-contingencies-remaining-purchase-commitments-details" name="statement-statement-note-9-commitment-and-contingencies-remaining-purchase-commitments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-note-9-commitment-and-contingencies-tables" name="statement-statement-note-9-commitment-and-contingencies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="qlys_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
