The discussion paper consists principally of two checklists of preoperational research needs for development projects in developing nations. (Preoperational research is focused on the possibility or feasibility of introducing a given innovation, its implications, and necessary modification.) The checklists, the first on factors relevant for agricultural program planners and the second on implications for a family planning project, group preoperational research needs as quantitative and qualitative data in nine categories: Kinship, economic and political and bureaucratic structure, legal system, educational system, medical/nutritional/sanitary beliefs and practices, religion and ethics, other cultural factors, and current exposure to other innovations. The author contends that it is useful to systematize needed information so that the social planner may be made aware of the multiplicity of factors affecting his projected input in a development activity, e.g., his introduction of new agricultural techniques or of a contraceptive device. (MF)