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  <xs:element id="ajg_InsuranceBrokerageManagementServicesMember" abstract="true" name="InsuranceBrokerageManagementServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_ExpirationListsMember" abstract="true" name="ExpirationListsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_BusinessCombinationContingentConsiderationLiabilityMeasurementPeriod" abstract="false" name="BusinessCombinationContingentConsiderationLiabilityMeasurementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ajg_BusinessCombinationAggregateEarnoutObligationMaximum" abstract="false" name="BusinessCombinationAggregateEarnoutObligationMaximum" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationAggregateEarnoutObligationRecordedMaximum" abstract="false" name="BusinessCombinationAggregateEarnoutObligationRecordedMaximum" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCashOrStockAtOption" abstract="false" name="BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCashOrStockAtOption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCash" abstract="false" name="BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCash" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessAcquisitionsPurchasePriceAllocationGoodwillAmount" abstract="false" name="BusinessAcquisitionsPurchasePriceAllocationGoodwillAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsExpirationLists" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsExpirationLists" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsNonCompeteAgreements" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsNonCompeteAgreements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsTradeNames" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsTradeNames" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_NumberOfEmployees" abstract="false" name="NumberOfEmployees" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ajg_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentGoodwill" abstract="false" name="BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentGoodwill" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_BusinessAcquisitionPurchasePriceAllocationGoodwillNotExpectedTaxDeductibleAmount" abstract="false" name="BusinessAcquisitionPurchasePriceAllocationGoodwillNotExpectedTaxDeductibleAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationAnnualizeRevenue" abstract="false" name="BusinessCombinationAnnualizeRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessAcquisitionsnetEarningsBeforeInterestIncomeTaxesDepreciationAmortizationAndChangeInEstimatedAcquisitionEarnoutPayables" abstract="false" name="BusinessAcquisitionsnetEarningsBeforeInterestIncomeTaxesDepreciationAmortizationAndChangeInEstimatedAcquisitionEarnoutPayables" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessAcquisitionActualRevenueAndPreTaxIncomeLossTable" abstract="true" name="BusinessAcquisitionActualRevenueAndPreTaxIncomeLossTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ajg_BusinessAcquisitionActualRevenueAndPreTaxIncomeLossLineItems" abstract="true" name="BusinessAcquisitionActualRevenueAndPreTaxIncomeLossLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalentsAndRestrictedCash" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalentsAndRestrictedCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFiduciaryAssetsCurrent" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFiduciaryAssetsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFiduciaryLiabilitiesCurrent" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFiduciaryLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest" abstract="false" name="BusinessAcquisitionsProFormaNetIncomeLossToControllingInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_RiskManagementSegmentMember" abstract="true" name="RiskManagementSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_ChangeInContractWithCustomerLiabilityRollForward" abstract="true" name="ChangeInContractWithCustomerLiabilityRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_ContractWithCustomerLiabilityAdditions" abstract="false" name="ContractWithCustomerLiabilityAdditions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_NetChangeInCollectedBillingsAndDepositsReceivedFromCustomers" abstract="false" name="NetChangeInCollectedBillingsAndDepositsReceivedFromCustomers" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_ContractWithCustomerImpactOfChangeInForeignExchangeRates" abstract="false" name="ContractWithCustomerImpactOfChangeInForeignExchangeRates" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_SeniorUnsecuredNoteMember" abstract="true" name="SeniorUnsecuredNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_NotePurchaseAgreementMember" abstract="true" name="NotePurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_CreditAgreementWithPeriodicPaymentsOfInterestAndPrincipalExpiresApril32030Member" abstract="true" name="CreditAgreementWithPeriodicPaymentsOfInterestAndPrincipalExpiresApril32030Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_PremiumFinancingDebtFacilityMember" abstract="true" name="PremiumFinancingDebtFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_DebtLongTermAndShortTermCombinedAmountGross" abstract="false" name="DebtLongTermAndShortTermCombinedAmountGross" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_DebtInstrumentUnamortizedDiscountAndDebtIssuanceExpense" abstract="false" name="DebtInstrumentUnamortizedDiscountAndDebtIssuanceExpense" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_FixedRatesOfFourPointEightFivePercentBalloonDueFebruaryThirteenTwoThousandTwentySixMember" abstract="true" name="FixedRatesOfFourPointEightFivePercentBalloonDueFebruaryThirteenTwoThousandTwentySixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_FixedRateOfFourPointSevenThreePercentBalloonDueFebruaryTwentySevenTwoThousandTwentySixMember" abstract="true" name="FixedRateOfFourPointSevenThreePercentBalloonDueFebruaryTwentySevenTwoThousandTwentySixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_FixedRatesOfFourPointFourPercentBalloonDueJuneSecondTwoThousandTwentySixMember" abstract="true" name="FixedRatesOfFourPointFourPercentBalloonDueJuneSecondTwoThousandTwentySixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_FixedRateOfFourPointThreeSixPercentBalloonDueJuneTwentyFourTwoThousandTwentySixMember" abstract="true" name="FixedRateOfFourPointThreeSixPercentBalloonDueJuneTwentyFourTwoThousandTwentySixMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding" abstract="false" name="WeightedAverageNumberOfCommonAndCommonEquivalentSharesOutstanding" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ajg_AnnualActivityOfStockOptionPlansTable" abstract="true" name="AnnualActivityOfStockOptionPlansTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ajg_LongTermIncentivePlanMember" abstract="true" name="LongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_BlackScholesOptionPricingModelMember" abstract="true" name="BlackScholesOptionPricingModelMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_StockOptionPlansLineItems" abstract="true" name="StockOptionPlansLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_PeriodForOptionsToExpireFromDateOfGrant" abstract="false" name="PeriodForOptionsToExpireFromDateOfGrant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ajg_AgeOfEmployeeNoLongerSubjectToAwardForfeitureOnConditionCompliance" abstract="false" name="AgeOfEmployeeNoLongerSubjectToAwardForfeitureOnConditionCompliance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ajg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisedInPeriodIntrinsicValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedAndExpectedToVestNumberOfShares" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedAndExpectedToVestNumberOfShares" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ajg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedAndExpectedToVestExercisableWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedAndExpectedToVestExercisableWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="ajg_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" abstract="false" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ajg_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_Range03Member" abstract="true" name="Range03Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_Range04Member" abstract="true" name="Range04Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_Range05Member" abstract="true" name="Range05Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_Range06Member" abstract="true" name="Range06Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_Range07Member" abstract="true" name="Range07Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_Range08Member" abstract="true" name="Range08Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_InvestmentsAndEmployeeDeferredCompensationPlanTable" abstract="true" name="InvestmentsAndEmployeeDeferredCompensationPlanTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="ajg_DeferredEquityParticipationPlanMember" abstract="true" name="DeferredEquityParticipationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_DeferredCashParticipationPlanMember" abstract="true" name="DeferredCashParticipationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_InvestmentsAndEmployeeDeferredCompensationPlanLineItems" abstract="true" name="InvestmentsAndEmployeeDeferredCompensationPlanLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_UnearnedDeferredCompensationValue" abstract="false" name="UnearnedDeferredCompensationValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_UnearnedDeferredCompensationShare" abstract="false" name="UnearnedDeferredCompensationShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ajg_CompensationApprovedByCommitteeValue" abstract="false" name="CompensationApprovedByCommitteeValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_CashAndEquityAwardWithAggregateFairValueVestedAndDistributedToParticipants" abstract="false" name="CashAndEquityAwardWithAggregateFairValueVestedAndDistributedToParticipants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_RestrictedStockRestrictedStockUnitsAndPerformanceUnitAwardsMember" abstract="true" name="RestrictedStockRestrictedStockUnitsAndPerformanceUnitAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_EmployeeEmployedByAssuredPartnersMember" abstract="true" name="EmployeeEmployedByAssuredPartnersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_FormerAssuredPartnersEmployeeEmployedWithGallagherMember" abstract="true" name="FormerAssuredPartnersEmployeeEmployedWithGallagherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_CommonStockOptionsRestrictedStockWarrantsAndChangesInCapitalizationLineItems" abstract="true" name="CommonStockOptionsRestrictedStockWarrantsAndChangesInCapitalizationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_InterestOnDebtMember" abstract="true" name="InterestOnDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="ajg_OperatingLeaseObligationMember" abstract="true" name="OperatingLeaseObligationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_SubleaseArrangementsMember" abstract="true" name="SubleaseArrangementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_OutstandingPurchaseObligationsMember" abstract="true" name="OutstandingPurchaseObligationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_ContractualObligationsMember" abstract="true" name="ContractualObligationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_CommitmentsContingenciesAndOffBalanceSheetArrangementsLineItems" abstract="true" name="CommitmentsContingenciesAndOffBalanceSheetArrangementsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ajg_RecordedUnconditionalPurchaseObligationReceivableWithinOneYear" abstract="false" name="RecordedUnconditionalPurchaseObligationReceivableWithinOneYear" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_RecordedUnconditionalPurchaseObligationReceivableInSecondYear" abstract="false" name="RecordedUnconditionalPurchaseObligationReceivableInSecondYear" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_RecordedUnconditionalPurchaseObligationReceivableInThirdYear" abstract="false" name="RecordedUnconditionalPurchaseObligationReceivableInThirdYear" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_RecordedUnconditionalPurchaseObligationReceivableInFourthYear" abstract="false" name="RecordedUnconditionalPurchaseObligationReceivableInFourthYear" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_RecordedUnconditionalPurchaseObligationReceivableInFifthYear" abstract="false" name="RecordedUnconditionalPurchaseObligationReceivableInFifthYear" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="ajg_LettersOfCreditMember" abstract="true" name="LettersOfCreditMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearOne" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearOne" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearTwo" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearTwo" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThree" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThree" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFour" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFour" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFive" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearFive" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThereafter" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitmentsWithinYearThereafter" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_AmountOfCommitmentExpirationOffBalanceSheetCommitments" abstract="false" name="AmountOfCommitmentExpirationOffBalanceSheetCommitments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_CashAndCashEquivalentsExcludingRestrictedCash" abstract="false" name="CashAndCashEquivalentsExcludingRestrictedCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_CashCashEquivalentsRestrictedCashAndFiduciaryCash" abstract="false" name="CashCashEquivalentsRestrictedCashAndFiduciaryCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_QualifiedContributorySavingsAndThriftFourZeroOneKPlanMember" abstract="true" name="QualifiedContributorySavingsAndThriftFourZeroOneKPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ajg_CashAndCashEquivalentsRestrictedCashAndFiduciaryCash" abstract="false" name="CashAndCashEquivalentsRestrictedCashAndFiduciaryCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_IncreaseDecreaseInInvestmentIncomeDividend" abstract="false" name="IncreaseDecreaseInInvestmentIncomeDividend" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ajg_DefinedBenefitPlanPercentageOfEligibleCompensationForMatchingContributionsByEmployer" abstract="false" name="DefinedBenefitPlanPercentageOfEligibleCompensationForMatchingContributionsByEmployer" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ajg_MatchingContributionsVestingSchedule" abstract="false" name="MatchingContributionsVestingSchedule" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ajg_DefinedBenefitPensionPlanReversalOfDeferredTaxAsset" abstract="false" name="DefinedBenefitPensionPlanReversalOfDeferredTaxAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
