Is preparing for war the best means of preserving peace? In Sisters in Peace, Kate Laing contends that this question has never been solely the concern of politicians and strategists. She maps successive generations of twentieth-century women who were eager to engage in political debate even though legislative and cultural barriers worked to exclude their voices. In 1915, during the First World War, the Women's International Congress at The Hague was convened after alarmed and bereaved women from both sides of the conflict insisted that their opinions on war and the pathway to peace be heard. From this gathering emerged the Women's International League for Peace and Freedom (WILPF), which to this day campaigns against militarism and nuclear weapons. In Australia, the formation of a section of WILPF connected political women to a worldwide network that sustained their anti-war activism throughout the last century. In examining the rise of WILPF in Australia, Sisters in Peace provides a gendered history of this country's engagement with the politics of internationalism. This is a history of WILPF women who committed to peace activism even as Australia's national identity and military allegiances shifted over time-a history that has until now been an overlooked part of the Australian peace movement.