We are faced by astonishing legal ambivalences. International cooperation has led in the past few years to disappointments, and in the European Union has triggered considerable centrifugal forces. Having said that, the dense, institutional cooperation between the states constitutes the legal achievement of the past century par excellence, and as such is indispensable. Many instances of supranational cooperation have been created by the law, and act through the law. The consequence is a multiplicity of sources of the law, and this makes it difficult to comply with the law, whilst also posing an obstacle to international cooperation. This gives rise to the elemental question of how law and supranational cooperation can be enhanced. There are naturally no patent recipes or across-the-board solutions here. Nonetheless, the sustained will to uphold the law and to maintain a concept of codification which spans sources of the law, incorporating the rationality of the respective source of the law, could take on central significance. The role to be played by the lawyer in our time is that of coordinating the law. The digitalisation of the law, and the possibility of automatically enforcing it, thus provides a major opportunity to secure both the law and suprastate cooperation. The article forms an attempt to refine and re-enliven the codification concept in an age of modern diversity of sources of law.