Bethlem Royal Hospital is Britain’s oldest and arguably foremost mental hospital; a centre of psychiatric innovation notable for its early acceptance of voluntary, predominantly middle-class, patients. The study begins with the 1930 Mental Treatment Act, which endorsed voluntary and outpatient psychiatric treatment, and ends with the 1983 Mental Health Act, which placed legal controls on certain therapies, and introduced the Mental Health Act Commission. Although not wholly representative of other institutions, scrutiny of Bethlem can inform debates on the flux of ideas and methods within twentieth-century psychiatry, and further knowledge of the hospital in this era. The primary research aim is to analyse the changing nature of institutional care for psychiatric patients in mid twentieth-century Britain, through a case study of Bethlem Royal Hospital. Secondary objectives are to: * Explore the role of legislative frameworks in shaping the institution in terms of admissions and governance; * Investigate changing definitions of mental illness through analysis of the composition of patients with respect to their diagnosis and social factors; * Examine the impact of scientific developments in the theory and practice of psychiatry on service organisation and treatment. At the local level, combined admissions data and qualitative evidence provide a detailed, contextualised account of the Bethlem inpatient ‘journey’. Four national level themes emerged: first, a consumerist model of mental health was evidenced through hospital marketing materials, and, reciprocally, the preferences of patients and their families. A second key theme was a mid twentieth-century transition from aetiologic to diagnostic frameworks of mental illness. Thirdly, gender-specific attributions and treatment observed in interwar records were followed, in subsequent decades, by signs of a ‘meeting of minds’ in recorded experiences of male and female inpatients. Finally, this thesis addresses how changes in patients’ backgrounds, knowledge, and expectations, were intertwined with the development of psychotherapeutic approaches.