The items in this series relate to two major projects Riegel conducted in Europe between 1950 and 1952. The first one focused on public opinion in West Germany on a variety of topics, but emphasised government and politics in particular. This project was conducted with assitance in the form of a grant, stipend, and paid travel by the State Departnment. The second project, through Princeton University, focused on the impact of the cross cultural exchange program between Belgium and the United States, with the goal of understanding the opinion Belgians had of the United States after going through the program and then returning to their home country. Contents in this series include: Survey materials from both projects, information on participants in the Belgium study, publications Riegel kept from his time in Europe, his notes on the projects, and financial papers relevant to the projects.