This chapter outlines some of the themes, questions, and controversies that should be on the agenda of academics and policy-makers who are interested in the privatisation of punishment in Europe. It provides an overview of some important developments across the globe. The chapter addresses whether the privatisation of punishment has delivered on its promises: is it cost-effective and does it results in improved quality? It discusses some of the drivers behind the privatisation of punishment. The chapter reflects on the question: what role– if any – is there for private involvement in the practice of punishment? In many countries, private actors play an active role in the development and running of the detention centers. Even in times when punishment had become 'public' and a part of the rights of a state body, significant aspects of punishment and the implementation of sentences stayed in private hands. The chapter also presents an overview on the key concepts discussed in this book.