This book is a study of cultures of surveillance, from CCTV to genetic data-gathering and the new forms of subjectivity and citizenship that are forged in such cultures. It studies data, bodies and space as domains within which this subjectivity of the vulnerable individual emerges. The book also proposes that we can see a shift within cultures of surveillance where, from active participation in the process of surveilling, a witness-citizen emerges. The book therefore seeks to alter surveillance as a mere top-down system, instead arguing that surveillance is also a mode of engagement with the world enabling trust, accountability and eventually a responsible humanitarianism.