The comprehensive high school model emerged from the early 20th century struggle for a unitary as opposed to a dual system of secondary education and was outlined in the report of the Commission on the Reorganization of Secondary Education, The Cardinal Principles of Secondary Education (1918). In this study, Wraga traces the development of the model in the United States, evaluating (among other things) the influence of sociopolitical forces on the historical interpretations of the model. In the first book-length historical study of the comprehensive high school, he assesses the impact of successive reform movements on the model and offers recommendations for enhancing its effectiveness.