This thesis attempts to provide a detailed account of the process by which medical supervision of the health of school children became established in England and Wales. The analysis focuses primarily on the foundation of the School Medical Service in 1907 and its subsequent history. Although the School Medical Service itself is sometimes regarded as a consequence of the fears about the national condition aroused by the South African War, evidence suggests that the earliest attempts to monitor the physical condition of school children occurred during the school board era, when the links between health and nutrition and educational performance became apparent. A consequence of the ad hoc development of work in the field of school hygiene during this period was the emergence of a number of political, professional and even personal disputes following the establishment of the School Medical Service nationally. These meant that uniformity of"standards and of administration had not been achieved by the outbreak of the First World War. Particular difficulties were encountered in London, which is the subject of a special study. Despite these, there was a gradual growth in medical treatment and other non-mandatory services, resulting in the creation of an entirely new agency of treatment; the school clinic. The demands for doctors for military duties in the First World War curtailed some of the work of the School Medical Service, but treatment facilities continued to expand. After the war, the passage of legislation affecting all aspects of the Service marked the end of the first phase in the creation of a national system of health care for school children. The study concludes by attempting to assess the significance of the establishment of the School Medical Service, and its impact during the first stage of its development.