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  <xs:element id="wst_DebtInstrumentRatioOfDebtToEBITDA" abstract="false" name="DebtInstrumentRatioOfDebtToEBITDA" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="wst_ContractWithCustomerLiabilityRevenueRecognizedFromDeferredIncome" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedFromDeferredIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_SeniorCNotesDue2027Member" abstract="true" name="SeniorCNotesDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_CreditAvailableForTheIssuanceOfLettersOfCredit" abstract="false" name="CreditAvailableForTheIssuanceOfLettersOfCredit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_NetSalesMember" abstract="true" name="NetSalesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_ContractWithCustomerLiabilityIncreaseDecreaseDueToAdditionalCashPayments" abstract="false" name="ContractWithCustomerLiabilityIncreaseDecreaseDueToAdditionalCashPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_DeferredFederalStateAndLocalIncomeTaxExpenseBenefit" abstract="false" name="DeferredFederalStateAndLocalIncomeTaxExpenseBenefit" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_StandardPackagingMember" abstract="true" name="StandardPackagingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_CreditFacilityIsAvailableForSwingLineLoans" abstract="false" name="CreditFacilityIsAvailableForSwingLineLoans" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="wst_DefinedBenefitPlanExpectedFutureBenefitPayments" abstract="false" name="DefinedBenefitPlanExpectedFutureBenefitPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentAndCumulativeChangesInNetGainLossFromCashFlowHedgesEffect" abstract="false" name="AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentAndCumulativeChangesInNetGainLossFromCashFlowHedgesEffect" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_ContractWithCustomerAssetIncreaseDecrease" abstract="false" name="ContractWithCustomerAssetIncreaseDecrease" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="wst_ScheduleOfIntangibleAssetsByMajorClassTable" abstract="true" name="ScheduleOfIntangibleAssetsByMajorClassTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
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  <xs:element id="wst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumberOfSharesIssuableUponVesting" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestNumberOfSharesIssuableUponVesting" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
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  <xs:element id="wst_ScheduleOfOtherIncomeAndExpenseByComponentTableTextBlock" abstract="false" name="ScheduleOfOtherIncomeAndExpenseByComponentTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="wst_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployeePerYear" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesPerEmployeePerYear" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
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  <xs:element id="wst_ScheduleOfChangesInFairValueOfPlanAssetsProjectedBenefitObligationsAndNetFundedStatusTableTextBlock" abstract="false" name="ScheduleOfChangesInFairValueOfPlanAssetsProjectedBenefitObligationsAndNetFundedStatusTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
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  <xs:element id="wst_RevolvingCreditFacilityDue2024Member" abstract="true" name="RevolvingCreditFacilityDue2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_ReductionInNumberOfSharesAvailableForGrantForEachAwardGranted" abstract="false" name="ReductionInNumberOfSharesAvailableForGrantForEachAwardGranted" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="wst_LegalMattersContingenciesAndLegalCostsPolicyTextBlock" abstract="false" name="LegalMattersContingenciesAndLegalCostsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
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  <xs:element id="wst_AwardTypesOtherThanStockOptionsAndStockAppreciationRightsMember" abstract="true" name="AwardTypesOtherThanStockOptionsAndStockAppreciationRightsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="wst_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdjustmentsAboveBelowTargetWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdjustmentsAboveBelowTargetWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
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  <xs:element id="wst_OtherCurrentLiabilitiesAbstract" abstract="true" name="OtherCurrentLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="wst_ComputerHardwareAndSoftwareMember" abstract="true" name="ComputerHardwareAndSoftwareMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_DeferredTaxAssetsLeasingArrangements" abstract="false" name="DeferredTaxAssetsLeasingArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="wst_DefinedBenefitPlanUltimateHealthCareCostTrendRateNetPeriodicBenefitCost" abstract="false" name="DefinedBenefitPlanUltimateHealthCareCostTrendRateNetPeriodicBenefitCost" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
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  <xs:element id="wst_CostInvestmentImpairment" abstract="false" name="CostInvestmentImpairment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="wst_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYearNetPeriodicBenefitCost" abstract="false" name="DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYearNetPeriodicBenefitCost" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
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  <xs:element id="wst_NotesPayableAndOtherDebtCurrent" abstract="false" name="NotesPayableAndOtherDebtCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="wst_DaikyoSeikoLtdDaikyoMember" abstract="true" name="DaikyoSeikoLtdDaikyoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_WestCompanyMexicoSADeCVMember" abstract="true" name="WestCompanyMexicoSADeCVMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_LesseeOperatingLeaseOptionToTerminateTerm" abstract="false" name="LesseeOperatingLeaseOptionToTerminateTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="wst_ShareBasedCompensationArrangementsByShareBasedPaymentAwardNonOptionEquityInstrumentsVestedAndExercisableWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardNonOptionEquityInstrumentsVestedAndExercisableWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
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  <xs:element id="wst_StockSettledPSUAwardsMember" abstract="true" name="StockSettledPSUAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_HighValueProductComponentsMember" abstract="true" name="HighValueProductComponentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_ScheduleOfIntangibleAssetsByMajorClassTableTextBlock" abstract="false" name="ScheduleOfIntangibleAssetsByMajorClassTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="wst_StockOptionAndAppreciationRightsMember" abstract="true" name="StockOptionAndAppreciationRightsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_CashSettledPSUAwardsMember" abstract="true" name="CashSettledPSUAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_DeferredCompensationArrangementWithIndividualNumberOfPlans" abstract="false" name="DeferredCompensationArrangementWithIndividualNumberOfPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="wst_PurchasesAndRoyaltyPaymentsFromEquityMethodInvestees" abstract="false" name="PurchasesAndRoyaltyPaymentsFromEquityMethodInvestees" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_The2022RestructuringPlanMember" abstract="true" name="The2022RestructuringPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_PerformanceVestingSharesOrUnitsDividendEquivalentsMember" abstract="true" name="PerformanceVestingSharesOrUnitsDividendEquivalentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_OtherIncomeExpense" abstract="false" name="OtherIncomeExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_EmployeeStockPurchasePlanEsppMember" abstract="true" name="EmployeeStockPurchasePlanEsppMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_ShareBasedCompensationArrangementByShareBasedPaymentAwardActualPayoutPercentage" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardActualPayoutPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wst_DefinedBenefitPlanPlanAssetsContributionsByEmployerNetOfPremiums" abstract="false" name="DefinedBenefitPlanPlanAssetsContributionsByEmployerNetOfPremiums" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_PatentsAndLicensingMember" abstract="true" name="PatentsAndLicensingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_GenericsCustomersMember" abstract="true" name="GenericsCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_DeferredCompensationArrangementWithIndividualConversionUnit" abstract="false" name="DeferredCompensationArrangementWithIndividualConversionUnit" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="wst_DeferredCompensationArrangementWithIndividualShareEquivalentsBalance" abstract="false" name="DeferredCompensationArrangementWithIndividualShareEquivalentsBalance" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationPensionSettlementPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationPensionSettlementPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="wst_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantsInPeriodWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantsInPeriodWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="wst_AssetRelatedChargesMember" abstract="true" name="AssetRelatedChargesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_AccruedSalariesWagesAndBenefitsCurrent" abstract="false" name="AccruedSalariesWagesAndBenefitsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_ScheduleOfIntangibleAssetsByMajorClassLineItems" abstract="true" name="ScheduleOfIntangibleAssetsByMajorClassLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="wst_WeightedAverageSharesOutstandingAbstract" abstract="true" name="WeightedAverageSharesOutstandingAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
</xs:schema>
