This book offers a sustained study of on one feature of a prison officer's job: 'doing' coercion. Adopting an interactionist perspective, the book presents research based on one-and-a-half-years of participant observation within an Italian custodial complex hosting both a prison and forensic psychiatric hospital, together with visual methods and interviews with staff. With a focus on the lawful, yet problematic and discretional threatening and 'doing' of coercion this volume contributes to the growing scholarly debate on power in a prison setting and the developing field of the micro-sociology of violence and of radical interactionism.