C.I.A.M. (Congrès internationaux d'architecture moderne). Founded in 1928 by Hélène de Mandrot, Sigfried Giedion, and Le Corbusier, C.I.A.M. sought to divert architecture from academic preoccupations. The organization was the major instrument for propagating avant-garde ideas in architecture and town planning during the periods from 1930 to 1934 and from 1950 to 1955. The early congresses stressed rigid functional zoning and a single type of urban housing; at subsequent meetings members reacted against inflexible and mechanical concepts of orderly planning. Internal conflict led to the group's eventual collapse after the Dubrovnik congress of 1956.