Using student-friendly features such as case studies and a glossary, this textbook provides an introduction to the concept of agency and how it can usefully inform social welfare practice. It considers how agency and power inter-relate and how it can inform new ways of thinking about the individual and society. Tracing the origins of agency and exploring the contributions of key thinkers from sociological and social policy perspectives, the book demonstrates a model of achievable change and in doing so represents an optimistic view on social work's potential to contribute to this. It is essential reading for students and professionals training in social welfare, social work and education.