When we go to the theatre, we understand that we are doing something different. It is not just that sitting and watching others for two hours (or performing for others' gazes) is different than other daily activities. It is that theatre itself is a particular social setting, obeying its own rules and operating by its own standards. That difference makes theatre feel free and unencumbered by many of the things that tie us to society and the world in the rest of our lives. And yet, of course, this feeling is misleading. Theatre may be distinct, but it is still connected to the wider world. Performances may be built out of the forms, ideas and material from the 'real world', and as audience members, we may take the experiences, stories, and insights we find in the theatre with us when we leave, and make use of them in our daily lives. How is it, then, that theatre is distinct from - and yet connected to - the social world around it? This book explores that question. We aim to describe the particular relationship that theatre has to the larger social world, how that relationship works, what it enables theatre to do, and how it can change.