Chapter 28 focuses on agent-based modelling. Agent-based models are computer programs composed of autonomous agents that are diverse and interact with one another and their environment. The program is simulated over time, exploring how the microlevel actions and interactions of many agents give rise to macrolevel patterns and dynamics. The chapter discusses the application of agent-based models to exploring emergent social-ecological systems (SES) outcomes and dynamics, policy assessment, the assessment of response of SES to environmental or social change, explaining emergent SES phenomena, and as boundary objects in participatory processes. It goes on to discuss the types of SES problems and research questions commonly addressed by this set of methods, as well as their limitations, resource implications and new emerging research directions. The chapter also includes an in-depth case study showcasing the application of agent-based modelling, and suggested further readings.