This dissertation is a case study of a public policy decision, the decision to shift the military manpower policy of the United States from conscription to a policy of complete volunteerism--the all-volunteer force. The case study approach is largely historical and is concentrated on the turbulent period between 1965, when the United States' combat role in South Vietnam escalated sharply, and 1973, the year of American withdrawal from the war and the last Selective Service System draft call. A brief history of the military manpower policy of the United States is outlined in order to set the case study period within the proper context and to permit a fuller understanding and appreciation of the policy decision. In order that the case study may have potential application to the study of other public policy decisions, a theoretical model for changes in public policy-making is developed based on the research of public policy-making theorists. This model, which is largely adapted from the theoretical work of ~he Agenda-Building Theorists, is compared to the events and inter-actions of key players in the case study. Although conclusions about a wider applicability of the model is not possible, it can be concluded that the theoretical model does fit the events and circumstances contained in the case study. In addition to attempting to derive a working theoretical model of change in public policy-making, a secondary purpose of the research is to address the nonnative aspects of the shift in policy from conscription to volunteerism. Based on the pattern of American military manpower policy, it appears that Anglo-Saxon liberalism, rooted in the freedom of the individual, is an extremely strong strain in American thinking, and that the relatively long period of conscription in the United States after World War II was an anomaly in the history of American military manpower policies. / Ph. D.