This article explores the use of a System Dynamics model as a boundary object in a case study regarding decision-making on water scarcity in South Africa. The model integrates expertise from the hydrological and ecological sciences with socio-economic information for a specific area, the Mossel Bay region. The model proved to be adaptable to multiple stakeholders, robust enough to maintain identity across stakeholders, and succeeded in allowing different stakeholders to work together without necessarily requiring consensus. This study supported communication between the stakeholders and enhanced the democratization of the decision-making processes by improving deliberation1 on contentious issues. Further applications of boundary spanning activities using system dynamics modeling in other cases is recommended.Policy AnalysisSystem Engineerin