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  <xs:element id="hsii_GeneralAndAdministrativeExpenseAdjusted" abstract="false" name="GeneralAndAdministrativeExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="hsii_CostsAndExpensesAdjusted" abstract="false" name="CostsAndExpensesAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
