There is little doubt that Europeanization is making headway now in the field of criminal justice. Some provisions of the Union Treaty (like Art.29, 31, 34 TEU) are at least an indication of the forces which are likely to shape future developments. There exist different possible lines of development: more intensive co-operation, assimilation and harmonisation, for example in the form of a model penal code or in form of the proposed Corpus Juris. They all have their weaknesses.