The Goods and Services Tax (GST) was introduced in Australia in July 2000 modelled on the European Union’s value-added tax (VAT) system at a relatively lower and flat rate of 10%. In recent years, debate over the efficacy of the GST, and the tax system in general, has intensified. This paper analyses the economics of alternative tax policy scenarios for the purpose of informing the tax debate in Australia. Our analytical framework applies a dynamic computable general equilibrium model of the Australian economy that has been specifically designed for policy analysis.