Under the direction of Henry Raymond, who took over from Henri Lefebvre, he contributed to the development of urban sociology and architecture according to historical approaches. Its third cycle thesis in sociology focused on the genesis of architectural space of the Renaissance (1981) and his thesis of State Humanities (1987) on the policy of paternalistic employer housing and urbanization of the industrial cities of nineteenth and twentieth centuries. Research professor in several universities and schools of architecture in France and abroad, particularly in North Africa, Prof. Frey continues to invest in stocks of cooperation to develop research training and research in science social, architecture and urbanism. His current research focuses on issues of urban morphology and social morphology as well as the history of urban planning theories and doctrines.