This contribution considers the development of codecision over the last 20 years from a practitioner's point of view, from inside the european parliament. It argues that the parliament has adapted its behaviour and increased resources to ensure that the procedure works well and has used its equal status with the council to influence legislative outcomes. However, this considerable achievement has not been without cost. Parliament has effectively been obliged to adjust to a diplomatic form of negotiations which is of limited interest to the wider public. In broader terms, we suggest that the development of the codecision procedure provides one test of the democratization of the european union. It points to the balance between the criteria of efficiency and transparency in the legislative process, underlining the weight that has been accorded to the former and the relative lack of attention paid to the latter.