CONTEXT: Livestock farming systems have received particular attention in the news and scientific media. However, do these considerations ever come to a real debate? Nothing is less certain. There is much attention on the negative impacts of livestock farming on the environment, and it remains difficult to have a fruitful dialogue on the desirable developments of livestock farming areas. This is also true at a local scale, where antagonisms among stakeholders can be strong. OBJECTIVE: We present La Grange®, a generic serious game that reveals trade-offs and synergies in livestock farming areas. Its aim is to promote horizontal knowledge and dialogue among stakeholders on locally-adapted transition for livestock farming. METHODS: After presenting the conceptual model underlying the game with the different game components and phases, we report the outputs of four case studies with groups of farmers or students in agriculture. RESULTS AND CONCLUSIONS :We show that La Grange® fills a gap in the toolbox for understanding livestock farming, making it possible to integrate generic and local knowledge and incorporating its biotechnical, environmental, economic, and sociocultural dimensions. In each case study, La Grange® not only revealed trade-offs and synergies between these dimensions, but also allowed new cooperation and strategic roadmaps to be set up for a livestock farming area. Both farmers and students perceived the game as a less top-down way of learning. When played with citizens, two of them joined the steering committee on an experimental farm after the game session. SIGNIFICANCE: As a low-tech, easy-to-access game, La Grange® can be easily used by extension services and agricultural teachers. Outputs from the four case-studies makes it possible to classify La Grange® as a “Game for Change” due to its impact on supporting sustainability.