This contribution covers the development of European administrative law, in particular the changes which the Treaty of Lisbon has brought about. Next to a growing amount of secondary law, EU administrative law has been mainly shaped by the Court of Justice of the European Union. However, it still lacks a coherent structure. The author, thus, pleads for the codification of the major rules on administrative procedures in particular in the field of indirect implementation of European law - on a yet to be established legal basis in the Treaties which - in his view - the Lisbon Treaty still does not provide for.