The five papers in this volume examine the methods, costs, and effects of traditional agricultural extension services and basic education and about the use of mass media for extension and education. The first paper, a literature review regarding the effectiveness of agricultural extension, reports that extension agents' studies of internal efficiency have been generally critical, while evaluators of external efficiency, mainly economists, show much more positive results. It is suggested that extension agents often have irrelevant evaluation criteria and economists generally overestimate the specific impact of extension services. The second paper reviews the literature on the comparative value of mass media and traditional approaches. Emphasis is on ways in which mass media have been used for agricultural extension and for basic education, ways in which mass media have been linked with group and individual study, and the costs of mass media as compared with alternatives. The remaining three papers discuss three different approaches to using mass media for rural education. These case studies focus on a government department, the Extension Aids Service of the Ministry of Agriculture of Malawi; a nongovernmental organization, INADES-Formation in West Africa; and a semigovernmental agency, the Lesotho Distance Teaching Centre. (YLB)