Railway regional passenger transport is experiencing since 1970 in France and Italy but also in the main European countries a decline in modal split facing car mobility. To inverse this trend, the regionalization of railway regional passenger transport is today implemented in France and Italy. This reform is still in both countries in process and will have some impacts on the regional service by opening the field to service's contracts between transport authorities and operators (only the national operator SNCF in France is allowed). In this paper, we will analyze the framework of regional railway passenger in France and Italy. We will then highlight the impact of the regionalization reform for both countries. We will show that regionalization is based on a double negotiation process : first, with the central State, it deals with the determining of financial grants due to this transfer of competence without transfer of charges. Secondly, it deals with a negotiation for establishing a convention Transport Authority / Regions and Operators. Organization and financing competence, communication, pricing, quality control will be competencies of the regions. We will then conclude by showing the challenge and limits of the reform. What are the brakes of the regionalization reform in France and Italy?