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  <xs:element id="step_CompensationExpenseCashBasedCompensationAndBenefits" abstract="false" name="CompensationExpenseCashBasedCompensationAndBenefits" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_AdjustmentsToAdditionalPaidInCapitalDeferredTaxEffect" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalDeferredTaxEffect" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_ClassB2UnitMember" abstract="true" name="ClassB2UnitMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_RevenueCarriedInterestAllocationMinimumReturnLevelsRequired" abstract="false" name="RevenueCarriedInterestAllocationMinimumReturnLevelsRequired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="step_PartnersCapitalDividendThreshold" abstract="false" name="PartnersCapitalDividendThreshold" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_CarriedInterestAllocationRevenuesMember" abstract="true" name="CarriedInterestAllocationRevenuesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_InfrastructureSubsidiaryMember" abstract="true" name="InfrastructureSubsidiaryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_RevenueCarriedInterestAllocationAsPercentageOfCumulativeFundOrAccountPerformance" abstract="false" name="RevenueCarriedInterestAllocationAsPercentageOfCumulativeFundOrAccountPerformance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="step_ManagementAndAdvisoryFeesNetFocusedCommingledFundsMember" abstract="true" name="ManagementAndAdvisoryFeesNetFocusedCommingledFundsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_ManagementAndAdvisoryFeesNetAdvisoryAndOtherServicesMember" abstract="true" name="ManagementAndAdvisoryFeesNetAdvisoryAndOtherServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_NumberOfClassesOfCommonStockOutstanding" abstract="false" name="NumberOfClassesOfCommonStockOutstanding" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="step_NoncashChangeInContingentConsideration" abstract="false" name="NoncashChangeInContingentConsideration" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_BlockerEntitiesMember" abstract="true" name="BlockerEntitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_IncentiveFeesSeparatelyManagedAccountsMember" abstract="true" name="IncentiveFeesSeparatelyManagedAccountsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_LesseeOperatingAndFinanceLeaseLiabilityToBePaidAfterYearFive" abstract="false" name="LesseeOperatingAndFinanceLeaseLiabilityToBePaidAfterYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_PerformanceFeeRelatedCompensationRelatedToCarriedInterestAllocation" abstract="false" name="PerformanceFeeRelatedCompensationRelatedToCarriedInterestAllocation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_ManagementAndAdvisoryFeesNetSeparatelyManagedAccountsMember" abstract="true" name="ManagementAndAdvisoryFeesNetSeparatelyManagedAccountsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_CarriedInterestAllocationFocusedCommingledFundsMember" abstract="true" name="CarriedInterestAllocationFocusedCommingledFundsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_ShareBasedCompensationArrangementByShareBasedPaymentAwardProfitsInterest" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardProfitsInterest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="step_CompensationAndBenefitsExpense" abstract="false" name="CompensationAndBenefitsExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_CumulativePercentageOwnershipAfterAllTransactions" abstract="false" name="CumulativePercentageOwnershipAfterAllTransactions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="step_StockIssuedDuringPeriodValueExchangeOfSecuritiesAndNewIssues" abstract="false" name="StockIssuedDuringPeriodValueExchangeOfSecuritiesAndNewIssues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_EquityMethodInvestmentAccruedCarriedInterestRelatedCompensationPayable" abstract="false" name="EquityMethodInvestmentAccruedCarriedInterestRelatedCompensationPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_DeferredTaxAssetsNetOfValuationAllowanceReorganizationAndInitialPublicOfferingTransactions" abstract="false" name="DeferredTaxAssetsNetOfValuationAllowanceReorganizationAndInitialPublicOfferingTransactions" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_NumberOfPartnershipUnitsAcquired" abstract="false" name="NumberOfPartnershipUnitsAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="step_LesseeOperatingAndFinanceLeaseLiabilityToBePaidYearFive" abstract="false" name="LesseeOperatingAndFinanceLeaseLiabilityToBePaidYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_PartnershipOfSubsidiaryMember" abstract="true" name="PartnershipOfSubsidiaryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_NumberOfSharesOwnedAfterAllTransactions" abstract="false" name="NumberOfSharesOwnedAfterAllTransactions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="step_DueToRelatedPartiesTaxReceivableAgreements" abstract="false" name="DueToRelatedPartiesTaxReceivableAgreements" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="step_PartnersCapitalMember" abstract="true" name="PartnersCapitalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_CarriedInterestAllocationSeparatelyManagedAccountsMember" abstract="true" name="CarriedInterestAllocationSeparatelyManagedAccountsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="step_StockholdersEquityUnitsExchangedInOfferingShares" abstract="false" name="StockholdersEquityUnitsExchangedInOfferingShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="step_StockholdersEquityEffectOfReorganizationShares" abstract="false" name="StockholdersEquityEffectOfReorganizationShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
</xs:schema>
