The principle that detention should be a measure of last resort is an important benchmark of children's rights. However, the obligations that this principle imposes upon States are unclear with little consistency in its application. This article examines the Australian experience illustrating the enduring tensions between formal commitments and detention practices at a State and Federal level. All governments in Australia claim some adherence to children's rights but commitments to making decisions in the best interest of the child or to using detention as a last resort have failed to prevent children from becoming the collateral damage of government attempts to exclude refugees or the explicit targets of various law and order campaigns. Children's rights are an important measure of the shortcomings of particular detention policies and regimes. However, they are likely to be a more effective tool for resisting the use and nature of detention when they reflect wider demands for social inclusion. Notes and references