Under the Starting Bases for the Reorganisation of Relations between Serbia and Montenegro, signed in Belgrade on March 14, 2002, the Federal Assembly on February 4, 2003 promulgated the Constitutional Charter of the State Union of Serbia and Montenegro.

The State Union is "based on the equality of the two member-states, the State of Serbia and the State of Montenegro." Under the Charter, the state union's flag, national anthem and coat-of-arms were defined in accordance with the law. The administrative centre of Serbia and Montenegro was in Belgrade. The bodies of the state union were the Assembly of Serbia and Montenegro, president of Serbia and Montenegro, Council of Ministers and Court of Serbia and Montenegro. The Assembly was monocameral. The Assembly president and vice president could not be from the same member-state. The president of the Assembly and president of Serbia and Montenegro could not be from the same member-state. The president of Serbia and Montenegro represented the State Union in the country and abroad and chaired the Council of Ministers, consisted of five ministries. The ministers of foreign affairs and defence were to swap with their deputies from the other member-state after two years.

The Constitutional Charter stressed that "upon the expiry of a three-year period, the member-states shall have the right to initiate the procedure for the alteration of the state status, that is for leaving the State Union of Serbia and Montenegro." Montenegro used this right, organised a referendum on May 21, 2006 and became an independent state.

List of Constituent Acts of Yugoslavia