According to the "Constitutional Economics", which formes the basic point of view of the application of the Public Choice Theory to the economic policy, it is essential to make an economic analysis of the behavior of the actors who take part in the political process in order to determine the constitutional level of the authorities of the state and the limits of the state. The view that dominated until the beginning of the 1970s in economics was that the state would be able to achieve desirable macroeconomic targets with active demand policies. However, developments that emerged in these years can not be explained by traditional economic theories have brought with it a doubt that they will lead to demand-oriented economic policies. The Constitutional Economics Approach, which finds its roots from the Social Contract Theory and Public Choice Theory, argues that the behavior of the units taking part in the political and economic field, questioning the active role of the state, can be transformed into arbitrary applications by acting from the Maximand primacy is regarded as an alternative to active economic policies. In this study, the foundations, assumptions and proposals of the theory of the Constitutional Economics will be examined, then the concept of transition economy will be explained and the role of the state in transition economies will be questioned and the importance of creating a fiscal constitution in this countries will be emphasized.

Keywords: Constitutional Economics, Public Choice Theory, Transition Economies, Fiscal Constitution.