3. CONCEPTUAL MODEL In this section, a conceptual model for the simulation-based performance evaluation and assessment of integrating spare parts supply chain planning and Intelligent Maintenance Systems is presented. In this stage the goal is to show relevant information to be used in the simulation and evaluation of methods, solutions and results adopted during the development of I2MS2C concept. This information will be used to validate the overall and integrated research result and provide a proof-of-concept, based on a real test case. The conceptual model is shown in the Figure 1.