This book investigates the historical development of British social policy regarding mental deficiency and the influence of eugenic thought on state intervention between 1870 and 1959. Mathew Thomson, a historian specializing in the social history of medicine, utilizes extensive archival research from central government records, health professional documentation, and local authority reports. He argues that the specific trajectory of British policy—characterized by segregation and community care rather than the compulsory sterilization seen elsewhere—was shaped primarily by the nation's inherent social conservatism and resistance to state intervention rather than a commitment to liberal humanitarian principles.

Historians and scholars of social policy identify this work as a definitive account of the institutionalization of mental health care in Britain. Readers frequently note the academic density of the prose and the meticulous use of primary source documentation to challenge conventional narratives regarding British liberalism.