This paper deals with the Institutions of the European Union in the draft Treaty establishing a Constitution for Europe (hereinafter: ‘the draft Constitution’) submitted to the European Council meeting in Thessaloniki on 20 June 2003. It describes these institutions and their task from a perspective of the Union's democratic legitimacy. The paper is based on a book entitled The European Union: a Polity of States and Peoples, which will be published by Stanford University Press and Hart Publishing, Oxford. In this book, I examine the democratic legitimacy of the European Union as a whole. The book parts from the proposition that the Union is a ‘body politic’ which develops into a federal system, however not a State, with a parliamentary consensual (non-majoritarian) form of government. In the meantime, the draft Treaty has been amended by the Inter-Governmental Conference (IGC) held in Brussels on 17/18 June 2004. In so far as the amendments relate to the subject of this paper, they are mentioned below in the text or the endnotes.