This thesis examines the development of Anglesey’s pioneering scheme of comprehensive education between 1935 and 1974. It scrutinises the contributing factors that permitted Anglesey to become the first local authority to introduce a fully comprehensive system of secondary education in 1953. The political process behind educational developments is analysed, with particular focus on the relationship between local and central government. Due to the island’s prominent role as a pioneer of comprehensive schooling, this local case study is also positioned within the wider educational context of the time. The broadly chronological approach of the study shows the Local Education Authority’s (LEA) early support of multilateralism, and its successful resistance to the desires of the Board of Education (BoE) throughout the 1930s and into the 1940s. The implementation of the pioneering scheme in 1953 demonstrated continuity rather than change. It is emphasised that the exceptional circumstances which existed on Anglesey was the predominant reason why such an experimental scheme was allowed to go ahead. The early introduction of a comprehensive system guaranteed Anglesey a prominent place within the broader educational debate during the 1950s and 1960s. The thesis evaluates the significant interest and scrutiny the education system engendered, and the interrelationship between local developments and the wider educational debate. This work reveals how issues were emerging in Anglesey’s comprehensive schools during the latter half of the 1960s and the early 1970s. It analyses how Anglesey’s comprehensive scheme was becoming a cause for concern locally, at the very time that central government expressed its official support for comprehensive schools. Paradoxically, the LEA’s reservations also coincided with Anglesey’s case being used in the national press to justify and strengthen comprehensive reform, showing the discrepancy between the focus of the national debate and the reality of comprehensive schooling in Britain at this time.