Abstract. In the domain of the fiscal politics characteristic to the unionist entities, the challenges of the harmonization process are multiple. The American model, which has situated the idea of the development of the federal state on the established principles of the participative federation, has represented the first step in this direction. The apparition of the European Union represents a new challenge in the domain of the state suzerainty and common politics. The article tries to answer to the question related to the possibility of application of a coherent fiscal policy at federal level.

Keywords: tax harmonization; tax competition; coordination; fiscal disparities; stabilization policy.