The Treaty establishing a Constitution for Europe was signed in Rome on 29 October 2004 by 53 senior political figures from the 25 member states of the European Union. In most cases heads of state designated plenipotentiaries to sign the treaty, but some presidents also signed on behalf of states which were republics. Most designated plenipotentiaries were prime ministers and foreign ministers.
Representatives of three candidate countries also signed the Final Act of the treaty as observers.
Croatian representatives attended the ceremony but did not sign.