It is attempted with this dissertation to draw an explanatory interdisciplinary framework to clarify the causes of systemic corruption. Following an intense review of political sciences, economics, and sociology literatures on the issue, a complex systems theoretical model is constructed. A political system consists of five main components: Society, interest aggregators, legislative, executive and private sector, and the human actors in these domains. It is hypothesized that when the legitimacy level of the system is low and morality of the systemic actors is flawed, selected political, social and economic incentives and opportunities that may exist within the structure of the systemic components might -individually or as a group- trigger corrupt transactions between the actors of the system. If left untouched, corruption might spread through the system by repetition and social learning eventually becoming the source of corruption itself. By eroding the already weak legitimacy and morality, it may increase the risk of corruption even further. This theoretical explanation is used to study causes of systemic corruption in the Turkish political system. Under the guidance of the complex systems theory, initial systemic conditions, -legacy of the predecessor of Turkey Ottoman Empire-, is evaluated first, and then political, social and economic factors …