I am a PhD candidate with Environmental Economics and Natural Resources Group, Section Economics, Wageningen University and Research, supervised by Andries Richter (Environmental Economics and Natural Resources Group), Machiel Lamers (Environmental Policy Group), and Ingrid van de Leemput (Aquatic Ecology and Water Quality Management). My research uses System Dynamics Models to unbox the complexity of tourism systems within Marine Protected Areas (MPAs), aiming to understand how these systems behave and evolve over time. I explore this complexity through two main lenses. First, I look at the investment-development mechanism, examining how investor behavior drives the development of tourism within MPAs. Second, I explore tourism modalities and their impacts, looking at how different forms of tourism shape outcomes within these systems. While the model I develop is general, it will be simulated using data from two cases in Indonesia: Raja Ampat MPA and Nusa Penida MPA. Through this approach, I hope to offer a clearer picture of how MPA tourism systems work, supporting more informed and adaptive management of these areas.