This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The main aim of the book is to explore the use of public spaces as event venues. The book explains this trend, explores the debates that surround it and, perhaps most importantly, and examines the outcomes for public spaces. It illustrates that, rather than merely an apt metaphor or analogy, the idea of cities as stages is now a reality. Urban parks, squares and streets are used as stages for a variety of commercially, community and politically-oriented events. The focus in the book is official events that are pre-planned and sanctioned by urban authorities. Many participatory events such as carnival are essentially street events which have long inhabited the public realm of cities. In the United Kingdom (UK), the fair and the fairground perhaps represent the most significant events staged in urban public spaces during the seventeenth, eighteenth and nineteenth centuries.