Pursuing current new trajectories in surveillance studies, this book explores, analyses and develops the concept of 'participatory surveillance', challenging dominant approaches that emphasise organisations, power relations and notions of 'Big Brother' in order to focus instead on the activities of individuals. With close attention to the on-line practices of users of social media sites such as Facebook, Twitter, Google+ and Foursquare, Participatory Surveillance offers an understanding of surveillance that makes room for practices that support, expand and facilitate everyday activities and social interactions as peer- or self-surveillance. By critically addressing the 'worst case scenarios' often envisaged with regard to surveillance and social media, Participatory Surveillance provides new concepts that unfold the empowering, playful and productive aspects of surveillance practices. In this manner, it enables us better to comprehend the reasons for which so many people engage in social media practices that are often characterized as invading privacy, or subject to exploitation at the hands of commercial corporations. Combining surveillance and social media theory, this book explores the manner in which today's web culture is connected to surveillance practices, thus providing an alternative framework within which to think about surveillance and revealing surveillance to be constituted less by an unpleasant, dominating gaze, than by a form of active participation for everyday social interaction.