This is an essential overview of the relationship between gender, surveillance and penal welfare strategies from a grass-roots perspective. It is not just a history of women police, but a key work that examines the history of women, gender and sexuality in the twentieth century. The first in-depth historical study of women’s police work across the twentieth century, it draws on a rich vein of sources including oral history interviews, autobiographies, and archival documents, as well as the popular press, literature and visual images. The topics covered include prostitution, the regulation of sexual violence, child abuse and neglect as well as uniform, plain clothes and undercover policing.