Tax refund entitlement for diplomatic missions and international organisations subject to certificates, undertakings, reciprocity, and conditions on goods. Specified international organisations and foreign diplomatic missions or consular posts may claim refund of state tax on supplies of goods or services subject to documentary conditions: a certificate from the international organisation confirming official use; for diplomatic missions, a Protocol Division certificate based on reciprocity, an undertaking for services, a certification for goods confirming use and a three-year non-disposal condition, repayment on breach, and cessation of refunds upon withdrawal of the Protocol Division certificate.