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  <xs:element id="wst_OtherComprehensiveIncomeLossDefinedBenefitPlanOtherCostsBeforeTax" abstract="false" name="OtherComprehensiveIncomeLossDefinedBenefitPlanOtherCostsBeforeTax" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_AssetsDefinedBenefitPlansNoncurrent" abstract="false" name="AssetsDefinedBenefitPlansNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_OtherMutualFundsMember" abstract="true" name="OtherMutualFundsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="wst_RestructuringAndRelatedCostsAssetImpairmentCharges" abstract="false" name="RestructuringAndRelatedCostsAssetImpairmentCharges" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_RestructuringAndRelatedActivitiesPeriodOfImplementation" abstract="false" name="RestructuringAndRelatedActivitiesPeriodOfImplementation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="wst_NumberOfManufacturingFacilitiesSold" abstract="false" name="NumberOfManufacturingFacilitiesSold" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="wst_The2022RestructuringPlanMember" abstract="true" name="The2022RestructuringPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="wst_RestructuringChargesCredits" abstract="false" name="RestructuringChargesCredits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_ExpirationPeriodAxis" abstract="true" name="ExpirationPeriodAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="wst_ExpirationPeriodDomain" abstract="true" name="ExpirationPeriodDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="wst_Year2025Member" abstract="true" name="Year2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_ThereafterMember" abstract="true" name="ThereafterMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationLitigationSettlementStateAndLocalAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationLitigationSettlementStateAndLocalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationRecognitionOfReservesForUnrecognizedTaxBenefitsAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationRecognitionOfReservesForUnrecognizedTaxBenefitsAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationTerminationOfPensionPlanAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationTerminationOfPensionPlanAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationDeferredTaxBenefitAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeferredTaxBenefitAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" 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_DeferredTaxAssetsRoyaltyAcceleration" abstract="false" name="DeferredTaxAssetsRoyaltyAcceleration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_DeferredTaxAssetsLeasingArrangements" abstract="false" name="DeferredTaxAssetsLeasingArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationRepatriationOfForeignEarningsNetOfForeignTaxCreditsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationRepatriationOfForeignEarningsNetOfForeignTaxCreditsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationRoyaltyAccelerationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationRoyaltyAccelerationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationPensionSettlementPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationPensionSettlementPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="wst_EffectiveIncomeTaxRateReconciliationUndistributedEarningsOfSubsidiariesPercentage" abstract="false" name="EffectiveIncomeTaxRateReconciliationUndistributedEarningsOfSubsidiariesPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="wst_OneCustomerMember" abstract="true" name="OneCustomerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_OtherEuropeCountriesMember" abstract="true" name="OtherEuropeCountriesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="wst_OtherCountriesMember" abstract="true" name="OtherCountriesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="wst_CorporateAndReconcilingItemsMember" abstract="true" name="CorporateAndReconcilingItemsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="wst_CostInvestmentImpairment" abstract="false" name="CostInvestmentImpairment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="wst_InterestIncomeExpenseAndOtherNonoperatingExpenseIncomeNet" abstract="false" name="InterestIncomeExpenseAndOtherNonoperatingExpenseIncomeNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
