Australia's goods and services tax (GST) was born of a political compromise and any discussion of potential changes to its scope and rate remains too sensitive for legislators to touch, particularly during an election year. But there's a growing realisation that GST reform could improve Australia's competitive advantage. So let the debate begin. Neil Warren, a professor of taxation at the Australian School of Business, looks at options and says the GST is a far more efficient tax than many existing levies. KPMG has been testing scenarios. Warren also notes that changing the GST would require all states to cooperate with the Commonwealth, something that's easier said than done.