Over the past 20 years, welfare conditionality - or the arrangements that require people to behave in particular ways in order to access welfare benefits, supports or services - has become an idea of considerable international interest, in the Global North and South. This new book in Routledge's Key Ideas series provides a comprehensive survey of this controversial but prevailing technique for welfare reform, informed by the latest research. It explains the history of the idea and its conceptual grounding in frameworks of power and social control. It considers its appeal across the political spectrum, discussing its use as a human development goal as well as a technique for welfare retrenchment. It explores how welfare conditionality is justified and contested from a range of perspectives and what its effects - intended or otherwise - are on the populations identified for its focus. Assessing the application of welfare conditionality to a range of social issues, including employment, housing, health and criminal justice, this is a balanced and wide-ranging text of sure interest to students, researchers, administrators and policy makers across the political and social sciences.