In this research an agent-based decision support system for service related maintenancehas been developed, the maintenance planning is complex including corrective andpreventive tasks of several non-associated plants. This type of problem is well suited formodeling and implementation using Agent-Based Modeling and Simulation (ABMS).The simulation model enables decision-makers to iteratively set parameters, runsimulations and evaluate results. Research shows that this approach can improve theunderstanding of the problem domain and also generate a basis for decision-making.