Concepts like freedom, equality and justice have many uses – and even more misuses. In seeking to manage an increasingly complex world, it is more important than ever to think carefully about the meaning of such concepts which are central to policy debates and integral to implementing effective social policy around the world. This concise and readable book is a guide to those essential social policy concepts. In addition to freedom, equality and justice, the book covers concepts like social risks and rights that are critical for understanding welfare states, and examines social policies through the lenses of power, recognition and investment. It also reflects on the role of social policy in addressing the biggest challenges that humanity faces in the twenty-first century, including the megatrends of inequality and climate change. Drawing on key works and examples from diverse contexts, this book will be of interest to undergraduate and postgraduate students of social policy, sociology, social work and other social sciences, as well as researchers, policymakers, practitioners and activists looking for an accessible introduction to the heart of social policy.