This book is about explaining surveillance processes and practises in contemporary society. Surveillance studies is a relatively new multi-disciplinary enterprise the aims to understand who watches who, how the watched participate in and sometimes question their surveillance, why surveillance occurs, and with what effects. This book brings together some of the world's leading surveillance scholars to discuss the 'why' question. The field has been dominated since the groundbreaking work of Michel Foucault, by the idea of panopticon and this book explores why this metaphor has been central in discussions of surveillance, what is fruitful in the panooptic approach and what are the possible approaches can throw better light on the phenomena in question. Since the advent of networked computer databases and especially since 9/11 questions of surveillance have come increasingly to the forefront of democratic political and policy debates in the global north and to an extent in the global South). Civil liberties democratic participation and privacy are some of the issues that are raised by these developments. But little progress can be made in responding to these issues without an adequate understanding of how, how well and whether or not surveillance works. This book explores the theoretical questions in a way that is grounded in and attuned to empirical realities.