Important results of a survey on "Information needs and information behavior in extension service in agriculture, home economics and nutrition" are given. This study was carried out by the Department for Economic and Social Sciences of the Technical University of Munich-Weihenstephan from May, 1979 to November, 1981. It revealed, by interviewing 14 leading personnel of documentation centers for nutrition, agriculture and forestry, that extension agents only form a very small sector of the centers' user. Various surveys using personal as well as written interviews and participant observation of extension agents resulted in a host of data on the determinants of extension agents' behavior toward information in general and "prophylactic" and "curative" in particular. Conclusions are drawn on optimal configurations of the future sources of information in the field of extension services in nutrition, home economics, and agriculture.