The Stop Huntingdon Animal Cruelty (SHAC) campaign arguably represents the high-water mark of animal rights activism in the UK in terms of impact and reach. It also represents one of the chapters in the history of animal rights activism in the UK in which some activists reached for significantly more radical strategies of action. Yet even here, we rarely see animal rights activists deploying physical interpersonal violence, and they never use lethal force. This paper traces the processes of restraint within the SHAC campaign and how these processes of restraint were shaped by developments both within the movement, and by the changing dynamics of activists’ interactions with a range of external actors, including the state, and the general public. The paper traces the evolution of these processes of restraint across three phases: the initial expansion of the campaign; the period of adaptation as activists responded to the control and repression strategies deployed by state actors and Huntingdon Life Sciences itself; and the long decline of the campaign after several of its leaders were arrested in 2008.