This book examines the policies, politics, and management of health care in Northern Ireland from 1921 to 1973, tracing its evolution from a fragmented, locally driven system to the most centrally managed model within the National Health Service. At its core is an analysis of the interest groups that championed change or resisted reform. It explores poor law, municipal, and voluntary provision in the interwar years, then considers the 1940s, shaped by wartime experience and Northern Ireland’s reluctant adoption of the welfare state. The discussion of the post-war decades highlights the complex relationship between health and politics and shows how the technocratic and managerialist reforms of the Terence O’Neill administration fractured unionist health policy in the years leading to the Troubles. Overall, the book offers original insights into Northern Ireland’s health care, politics, and modern history.