Questionnaires to determine the vocational and technical education needed by prospective workers in farming and in grain elevator and agricultural equipment businesses were administered to 20 workers in each of the jobs of (1) farm manager, (2) grain elevator manager, operator, salesman, and deliveryman, and (3) agricultural equipment manager, mechanic, salesman, and set-up man in randomly selected businesses in a 14-county area of east-central Illinois. Questionnaire items were categorized into seven knowledge areas: livestock, crops, soil fertility and management, agricultural resource conservation, agricultural mechanics, agricultural power and equipment, and agricultural business management. Workers in farming in the grain elevator and agricultural equipment businesses each needed differentiated knowledges within and among the seven agricultural knowledge areas. Thirty-eight instructional units were recommended for prospective workers for nine job categories in three kinds of agricultural businesses. Workers in seven of the nine agricultural job categories needed post-high school and continuing agricultural education. This Ph.D. thesis was submitted to the University of Illinois. (WB)