It's published online first on 27th April 2010. In advanced democracies, unions influence industrial relations through collective action and law. They also maintain influence in politics through their alliances with labour parties. But the weakness of some labour movements, most apparent in falling membership, raises questions about their capacity to shape future industrial relations policy, reach voters and maintain their party alliances. Drawing on literature in industrial relations and political sociology, this article provides a framework for understanding how the Australian union movement successfully campaigned against the conservative Howard government's labour laws called WorkChoices. We characterize the union movement's campaign — ...