The elaborate core is based on the presidential government system. Focusing on the USA, which is also the birthplace of the system, the type of this presidential system will be discussed in more depth. Firstly, the thesis will introduce the government system as a need emerged from social structure. On top of that, the importance of division of governance will be explained through historical landmarks. Clarifying the system structure and its development leads to the main part of the theis. Here, the thesis briefly reflects on parliamentary and semi-presidential systems. Furthermore, the main discussion focuses on development of the presidential system of government through history. The structure of the presidential system model will be analyzed by reflecting on its main characteristics and its pros and cons. Finally, the Republic of Croatia presidential system model will be discussed. Mainly, by focusing on the event of constitutional amendment in 2000. which fundamentally changed the governing system, transforming it from semi-presidential to parliamentary.