On 6 December 2006, the Iraq Study Group (ISG) issued its report on recommendations for US policy in Iraq in the future.
The BBC News website assesses the mandate of the ISG and the likely weight of its findings.
What is the ISG?
The 10-member panel of influential former US policy-makers and practitioners of international affairs focused on Iraq to come up with recommendations for policy-makers - including Congress and the White House.
It was co-chaired by former US Secretary of State James Baker - a Republican - and former Congressman Lee Hamilton, a Democrat. Among the participants were Lawrence Eagleburger, another former secretary of state, William Perry, a former secretary of defence, former Attorney General Edwin Messe, and a retired justice of the US Supreme Court, Sandra Day O'Connor.
The co-chairmen also decided to set up four working groups of 12 experts each - as well as to draw on the expertise and advice of a panel of retired senior military officials.
The panel was equally balanced between Republicans and Democrats.
When was it set up?
The ISG was launched on 15 March 2006 following a meeting on Capitol Hill. The original proposal of Virginia Republican representative Frank Wolf gained bipartisan backing in Congress.
"The country is divided, but a group of men and women of integrity and character [have] come together to take a fresh eye, a fresh approach," Congressman Wolf said at the launch.
What was it mandated to do?
No formal, or statutory, mandate was set for the panel. But Mr Baker told a news conference on 15 March that the purpose would be to "undertake a bipartisan, forward-looking assessment of the current and prospective situation on the ground in Iraq, its impact on the surrounding region and its consequences for United States' interests".
This was to include policy recommendations and advice. And ISG members directed their work - and that of the four working groups of experts they set up - to focus on four main issues:
- the strategic environment in Iraq and the surrounding region
- challenges to providing security in Iraq
- Iraq's political and democratic transition following elections
- economic reconstruction
In a letter to Congress on 7 April, the two chairmen stressed that their purpose was "to look forward, not to revisit past debates".
"We will assess the current situation in Iraq, and seek to develop insights and advice that might be of interest to the administration and Congress," the letter said.
It said the aim was "to draw on bipartisan voices and to seek bipartisan consensus".
Was the White House involved in setting it up?
No, the Bush administration was not directly involved, but it welcomed the development.
Who did the group meet?
The ISG began work on 11 April. It met or spoke to more than 170 individuals, including Iraq's leaders, President Bush, UK Prime Minister Tony Blair, ambassadors and other senior officials, analysts and media representatives from among Iraq's neighbours and the US.
Hundreds of others fed their suggestions to the four working groups, which have written analytical papers for the panel's benefit.
What is President Bush's position on the work of the group?
Speaking after a meeting with ISG members on 6 December, Mr Bush said he would take the report "very seriously".
He described the report as a "tough assessment" of the situation in Iraq and said his administration would consider its proposals and "act in a timely fashion".
The panel has conducted its work in private, in an effort to keep out of the political debate - especially in the run-up to US mid-term Congressional elections in November.
Therefore very little is known of the content of ISG interviews with Mr Bush, on 14 June and 13 November.
What does the ISG report say?
The report warns that the situation is "grave and deteriorating" and that there is no guaranteed path to success.
The report recommends that the US engage directly with two of Iraq's neighbours, Iran and Syria, to enlist their support for ending the insurgency.
The ISG backs a reduction in the number of US troops in Iraq - perhaps halving it from the current level of 140,000 - as well as changing the nature of their engagement from a combat to a back-up role.
"The primary mission of US forces should evolve to one of supporting the Iraqi army," the report says.
The report ends with a plea for a broad political consensus, predicting that without it US foreign policy is doomed to failure.
What weight is the ISG report likely to have?
The Iraq Study Group had no statutory mandate and its recommendations are not binding on Mr Bush.
Its authors have been at pains to suggest their role is advisory - it is up to President Bush and Congress to act on their recommendations should they so wish.
The bipartisan nature of the ISG findings is likely to receive a partisan reaction when the report becomes public.
Ahead of its publication, Mr Bush appeared keen to stress the panel's work was only one of many sources of advice on policy options over Iraq.
Indeed, his outgoing Defence Secretary Donald Rumsfeld has left him a "laundry list" of recommended adjustments. It is not known whether they will tally with the ISG priorities - or clash with them.
Democrats, by contrast, are expected to embrace the ISG recommendation to cut troop levels in the near future.
Perhaps the most telling harbinger of possible reaction may have been published by the Washington Times newspaper.
A commentary on the eve of the publication of the ISG report ran: "Tomorrow, an unelected, unaccountable and substantially unqualified commission will formally report what hasn't already been leaked about its recommendations with respect to the conflict in Iraq. The title of the commission is the Iraq Study Group. Given the nature of its contribution, a better name would be the 'Iraq Surrender Group'."
Mr Bush has entered the final two years of his presidency - and he knows that Iraq more than anything else will define his place in history.
He is also someone who bases his legacy on a demonstration of resolve and has stressed time and time again that he will not accept failure - and so may resist adopting the panel's recommendations if they are perceived as "surrender".
Is the ISG the only panel to have assessed Iraqi scenarios?
No, there are a number of such exercises - some expected to report in the near future. In the Pentagon, for instance, a group of colonels has been charged by the chairman of the joint chiefs to produce a fresh assessment of the Iraq situation.
Another such effort is taking place in the White House and the National Security Council.
Congress itself plans hearings that may produce further recommendations.
And there have been many other reviews of the Iraqi war both in the US and the UK - the main supporters of the war.
Few of their findings have become policy.