A common criticism of Australian politics is that it is largely concerned with conflict over practical issues, rather than with debate over sophisticated political ideas. James Walter’s new book, What Were They Thinking?, challenges this view by providing a wide-ranging account of the development of Australian political ideas from the late nineteenth century to the present. The book is structured around changes in the role of the state in Australia, moving from the early disputes over democracy and responsible government in the late nineteenth century, to the Australian settlement, postwar reconstruction and the neo-liberal reforms of the 1980s and 1990s, through to the recent controversy over the Global Financial Crisis. While the changing role of the Australian state over time is well-covered territory, Walter’s contribution is to focus on the intellectual arguments that have facilitated and accompanied these changes, and to bring them together in a systematic account.