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  <xs:element id="hli_DeferredTaxAssetsAccountsReceivableAndWorkInProcess" abstract="false" name="DeferredTaxAssetsAccountsReceivableAndWorkInProcess" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_DeferredTaxAssetsUSForeignTaxCreditsTollCharge" abstract="false" name="DeferredTaxAssetsUSForeignTaxCreditsTollCharge" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_DeferredTaxAssetsLeasingArrangements" abstract="false" name="DeferredTaxAssetsLeasingArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_DeferredTaxAssetsNonUS" abstract="false" name="DeferredTaxAssetsNonUS" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_CommonStockNumberOfClasses" abstract="false" name="CommonStockNumberOfClasses" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="hli_IncentivePlan2016Member" abstract="true" name="IncentivePlan2016Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="hli_IncentivePlan2006Member" abstract="true" name="IncentivePlan2006Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementbySharebasedPaymentAwardLiabilityClassifiedShareAwardActivityRollForward" abstract="true" name="SharebasedCompensationArrangementbySharebasedPaymentAwardLiabilityClassifiedShareAwardActivityRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwards" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwards" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsOffersToGrantInPeriod" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsOffersToGrantInPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedConvertedToCashPayments" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedConvertedToCashPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedTransferredToEquityGrants" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedTransferredToEquityGrants" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsForfeitedInPeriod" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsForfeitedInPeriod" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedTransferredToEquityGrantsShares" abstract="false" name="SharebasedCompensationArrangementByShareBasedPaymentAwardLiabilityClassifiedShareAwardsSharePriceDeterminedTransferredToEquityGrantsShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="hli_CommonStockVotingRightsNumberOfVotes" abstract="false" name="CommonStockVotingRightsNumberOfVotes" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="hli_CommonStockConversionRatioAtOptionOfHolder" abstract="false" name="CommonStockConversionRatioAtOptionOfHolder" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="hli_CommonStockAutomaticConversionRatioUponTransfer" abstract="false" name="CommonStockAutomaticConversionRatioUponTransfer" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="hli_Remeasurementofoperatingrightofuseassets" abstract="false" name="Remeasurementofoperatingrightofuseassets" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_NonCompensationExpense" abstract="false" name="NonCompensationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hli_RedeemableNoncontrollingInterestPurchasePeriod" abstract="false" name="RedeemableNoncontrollingInterestPurchasePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
</xs:schema>
