Stakeholder involvement in modeling studies is increasing. Fuzzy Cognitive Maps (FCMs) are emerging as a promising tool to provide a common base for stakeholders and modelers. FCMs developed by stakeholders from three local Mediterranean case studies are used to construct a stakeholder based FCM. This is done via a workshop in which the locally developed FCMs are merged by regional experts. Graphs and quasi-dynamic output are then compared with an FCM based on a mathematical model (WaterGAP). This model-based FCM was developed in a small workshop by WaterGAP modelers, based on their knowledge of the model. Results show that FCMs indeed have the ability to serve as a common base for linking participatory products and models. The quasi-dynamic output helps to get a better understanding of the commonalities and differences in the two system descriptions. The comparisons showed that FCM is a very promising tool for linking stakeholders and modelers. It can function as a common base for comparison and to illustrate differences between stakeholder perceptions and models in detail. The system dynamics of FCMs can play an important role in the comparison between system perspectives and the dissemination process.