Bibliography: leaves 113-135. This thesis investigates change in secondary schools in South Australia during the 1970s. Public concern about the purposes and organization of schools, and about education in general led to the establishment of a government enquiry in 1969, chaired by Peter Karmel. Its report, Education in South Australia, ushered in a period of rapid change. High schools and technical high schools were reshaped into comprehensive secondary schools. A significant element in this reform was the human capitalist idea that education is an investment in the development of the individual resulting in social and economic progress. This thesis examines the human capitalist basis of the reforms, the way in which child-centred open ideas were used in the reform of the curriculum and the impact of these on the schools.