A weed management support system, RiceWeed, was developed and included a knowledge base designed for rice producers in Arkansas. The system used several expert systems and compiled programs functioning as a single package to generate weed control recommendations. Each recommendation included a description of the treatment, an economic analysis, and a list of application comments. The economic calculations were based on a model of the yield impact of weeds in competition with the crop. Preliminary validation of system recommendations was accomplished using weed management scenarios observed in field verification studies conducted by extension personnel. This technique provided a basis for identifying a set of test scenarios that included common situations (that involved well-known, decision-making logic) and less common situations (that required special weed management expertise), distributed according to the frequency of occurrence in farmers’ fields. Preliminary user responses indicated a demand for weed management software and the information presented by RiceWeed.