Three papers are included in this document designed to provide English language information about characteristics and activities of Accion Cultural Popular (ACPO) a private, nonprofit organization concerned with improving the quality of life of rural populations and promoting rural development through mass media education programs. "Pioneer Radiophonic Education Programs of Latin America, 1947-1977" deals with ACPO's history, its Colombian context, its goals and objectives, its educational model, the role of teachers, and future directions of the organization. This paper describes the functions and interrelationship of the program's several components: radio messages, radiophonic schools, field personnel, textbooks, Peasant Library, weekly newspaper, recordings, and extension courses. Conceptual and practical considerations are summed up in "Mass Media in the Service of Colombian Rural Development"; emphasis is on Experience", emphasis is on coordination of multiple media, staff development, relevance of educational content, cultural influences, and implications of ACPO's private status and ties to the Catholic Church. "Communication Media for Rural Development" reports external research conducted to evaluate the impact of ACPO's educational activities on the socio-economic development of Colombia's isolated rural population. (JH)