Strategic and tactical decision support tools can assist farmers to make farm management decisions. The challenge facing researchers is to construct decision support tools that lead to the successful adoption of the strategies selected. This article describes and assesses the use of a whole-farm model in West African savannah regions. Farmers and advisors were involved in the choice and design of models, the definition and analysis of scenarios, the design of alternative strategies, and the validation of models. The validation process included a short and mid-term analysis of the use and usefulness of the model for farmers. During the validation process, farmers demonstrated that they were able to define and characterize iterative scenarios permitting the performance of their farm to be improved. They also had a good understanding of the outputs of the model, even several months after they had used the model. They declared having changed some technical or management practices and having acquiried calculation and management skills. This type of process offers an alternative to conventional advisory methods based on advisor expertise.