Iraq's US-appointed Governing Council has signed an interim constitution at a landmark ceremony in Baghdad. The BBC's correspondent in Baghdad, Barbara Plett, explains how the constitution works.
What is the interim constitution?
The interim constitution is a fundamental law that is supposed to govern Iraq during its transitional period. It will come into effect when the occupation authorities hand sovereignty to a caretaker government by the end of June. It will stay in place until an elected assembly can draw up a permanent constitution. That is supposed to happen in about a year's time.
What have been the sticking points delaying its signing?
The next formal step on the timetable is the actual handover of sovereignty
Generally, the main fault-line has been between the majority Shia Muslim Arabs and the minority Kurds. The former wanted a law with broad principles, in keeping with the view of their religious leadership that only an elected body should make key decisions about Iraq's future.
The Kurds wanted clear guarantees protecting their self rule in northern Iraq. They did not want to leave their fate in the hands of an elected body, which would be dominated by Arabs, most probably Shias.
Specifically, the Shias objected to a clause that could give the Kurds a de facto veto over the permanent constitution to be decided next year.
Are all the parties now satisfied with it?
Enough to sign it. The Shia politicians agreed to go ahead after Iraq's top Shia religious leader Ayatollah Ali al-Sistani indicated he would accept the text. But only after he expressed deep reservations. So the disagreements are still there.
And coming from a man of the ayatollah's stature, such reservations could further undermine the Governing Council, a body that already suffers from a lack of legitimacy in Iraqi eyes.
Also, since their meeting with the cleric, Shia politicians have signalled there is nothing in the interim constitution that cannot be changed in the permanent one - language that would cause concern for the Kurds.
What will be the next steps in the handover of US power?
The next formal step on the timetable is the actual handover of sovereignty. But no one knows to whom it will be transferred. The latest formula for selecting a caretaker government has been abandoned, so from now until the end of June the Iraqis and the coalition will have to come up with another one acceptable to all.
What does the document tell us about the kind of Iraq it envisages?
The document says the system of government in Iraq will be republican, democratic and pluralistic.
It has a comprehensive bill of rights. It provides for a federal state with two official languages - Arabic and Kurdish. It says Islam will be the official religion and a source of law, but not the primary source of law. And it says it aims for women to make up 25% of the national assembly to be elected next year.