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  <xsd:element id="seic_IncomeTaxesAttributableToNoncontrollingInterest" name="IncomeTaxesAttributableToNoncontrollingInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="seic_InformationProcessingAndSoftwareServiceFees" name="InformationProcessingAndSoftwareServiceFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InstitutionalInvestorsMember" name="InstitutionalInvestorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InterimCashDividendsMember" name="InterimCashDividendsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InternationalOperationsMember" name="InternationalOperationsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InvestmentAdvisorsMember" name="InvestmentAdvisorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InvestmentInUnconsolidatedAffiliateAbstract" name="InvestmentInUnconsolidatedAffiliateAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InvestmentInUnconsolidatedAffiliatesCondensedStatementsOfOperationsAbstract" name="InvestmentInUnconsolidatedAffiliatesCondensedStatementsOfOperationsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InvestmentManagersMember" name="InvestmentManagersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_InvestmentsInNewBusinessesMember" name="InvestmentsInNewBusinessesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_LSVAssetManagementMember" name="LSVAssetManagementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_LongTermDeferredIncomeTaxes" name="LongTermDeferredIncomeTaxes" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="seic_LongTermDeferredIncomeTaxesValuationAllowance" name="LongTermDeferredIncomeTaxesValuationAllowance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="seic_LsvEmployeeGroupIiMember" name="LsvEmployeeGroupIiMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_LsvEmployeeGroupIiiMember" name="LsvEmployeeGroupIiiMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_LsvEmployeeGroupMember" name="LsvEmployeeGroupMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_LsvEmployeeGroupMemberMember" name="LsvEmployeeGroupMemberMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_LsvSponsoredMutualFundsMember" name="LsvSponsoredMutualFundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_NumberOfDaysRightsBecomeExercisableFollowingPublicAnnouncement" name="NumberOfDaysRightsBecomeExercisableFollowingPublicAnnouncement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:normalizedStringItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_PercentageNotApproachedByExpectedReturnOnAnyVieInvestment" name="PercentageNotApproachedByExpectedReturnOnAnyVieInvestment" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_PrivateBankMember" name="PrivateBankMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_RightRedeemablePricePerRight" name="RightRedeemablePricePerRight" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element id="seic_RightsNonVotingRedeemableDays" name="RightsNonVotingRedeemableDays" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_RightsReceivedByCommonShareholderForEachCommonShareOutstandingRights" name="RightsReceivedByCommonShareholderForEachCommonShareOutstandingRights" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="seic_SaleOfMarketableSecurities" name="SaleOfMarketableSecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SaleOfSeiAssetKoreaAbstract" name="SaleOfSeiAssetKoreaAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_ScheduleOfTaxEffectOfTempoararyDifferencesRepresentingNetDeferredTaxAssetOrLiabilityTableTextBlock" name="ScheduleOfTaxEffectOfTempoararyDifferencesRepresentingNetDeferredTaxAssetOrLiabilityTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SecondRangeOfExercisePricesMember" name="SecondRangeOfExercisePricesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_SecuritiesAndAssetsOfEquivalentValuePurchasePricePerUnit" name="SecuritiesAndAssetsOfEquivalentValuePurchasePricePerUnit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="seic_SegmentReportingInformationOperatingMarginPercentage" name="SegmentReportingInformationOperatingMarginPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiAssetKoreaCoLtdMember" name="SeiAssetKoreaCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiInvestmentsDistributionCoSidcoMember" name="SeiInvestmentsDistributionCoSidcoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiInvestmentsEuropeLimitedMember" name="SeiInvestmentsEuropeLimitedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiPrivateTrustCompanyMember" name="SeiPrivateTrustCompanyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiSponsoredMutualFundsMember" name="SeiSponsoredMutualFundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SeiSponsoredOpenEndedMoneyMarketMutualFundsMember" name="SeiSponsoredOpenEndedMoneyMarketMutualFundsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfActivePlans" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfActivePlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_SoftwareDevelopmentCostUsefulLife" name="SoftwareDevelopmentCostUsefulLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_SoftwareRoyaltiesAndOtherInformationProcessingCosts" name="SoftwareRoyaltiesAndOtherInformationProcessingCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_StanfieldVictoriaSivMember" name="StanfieldVictoriaSivMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_SubadvisoryDistributionAndOtherAssetManagementCosts" name="SubadvisoryDistributionAndOtherAssetManagementCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_TaxPositionsRelatedToPriorYears" name="TaxPositionsRelatedToPriorYears" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_ThirdRangeOfExercisePricesMember" name="ThirdRangeOfExercisePricesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_TotalFromBusinessSegmentsMember" name="TotalFromBusinessSegmentsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_TransactionBasedAndTradeExecutionFees" name="TransactionBasedAndTradeExecutionFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_TwoThousandSevenCreditFacilityMemberMember" name="TwoThousandSevenCreditFacilityMemberMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_TwoThousandSevenPlanMember" name="TwoThousandSevenPlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_TwoThousandTwelveCreditFacilityMember" name="TwoThousandTwelveCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_UnitedStatesMember" name="UnitedStatesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_UnrecognizedTaxBenefitsDecreasesAndIncreasesResultingFromCurrentPeriodTaxPositions" name="UnrecognizedTaxBenefitsDecreasesAndIncreasesResultingFromCurrentPeriodTaxPositions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="seic_VariableInterestEntitiesInvestmentProductsAbstract" name="VariableInterestEntitiesInvestmentProductsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_VariableInterestEntitiesInvestmentProductsDisclosureTextBlock" name="VariableInterestEntitiesInvestmentProductsDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_VestingRateHigherSpecifiedDilutedEarningsPerShareTargetsAreAchieved" name="VestingRateHigherSpecifiedDilutedEarningsPerShareTargetsAreAchieved" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="seic_VestingRateWhenSpecifiedDilutedEarningsPerShareTargetsAreAchieved" name="VestingRateWhenSpecifiedDilutedEarningsPerShareTargetsAreAchieved" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
</xsd:schema>
