Wander Jager is a social scientist with a broad interdisciplinary interest in social complex phenomena and transition to a sustainable society. Many of his projects use Agent Based Simulation as a method, where behavioral theory and empirical data are integrated in computer simulations of social dynamics in populations. Applications address transitions in the energy sector, migration and acculturation, community projects, opinion dynamics and polarization, littering and team performance. These simulations are being used to explore possible dynamics and responses to policy, but also as a tool to help communities to reflect on their own future.