Paris, London, Madrid, New York and Moscow are battling to host the Olympics in 2012. Here, we give an overview of how the five bids compare.
PARIS (Odds to win: 1-5)
Paris is favourite after coming out on top in IOC reports assessing the candidate cities.
The French capital's venue plans, accommodation capacity and transport infrastructure received high praise from the inspectors.
World Cup 1998 was hailed as a great success and the Stade de France, the city's planned Olympic stadium, hosted the World Athletics Championships in 2003.
Paris can argue that it deserves the Games after continuing to bid despite losing out for 2008 and 1992.
The Stade de France will be 14 years old in 2012. Work would be needed to prepare it for the Games, and there has been criticism about bad sight lines when it is set up for athletics.
London and Madrid can both boast athletes' villages close to the key venues, whereas athletes would have to travel by bus to their events in Paris.
LONDON (Odds to win: 7-2)
London is perceived as having momentum, and the quality of its bid file was praised by the IOC inspectors.
The city offers strong claims for an Olympic legacy as it plans to regenerate a large area of land in the east of the city and build new sporting facilities.
London's bid team believe they have the best athletes' village, which will be right in the heart of their Olympic Park.
Manchester made a success of the Commonwealth Games in 2002.
London will need to hammer home the message that it can deliver its venue and transport plans, and that the general public fully backs the bid.
The aborted campaign to host the 2005 World Athletics Championships - London pulled out after a row over the proposed site at Picketts Lock - dented its international sporting standing.
There has also been confusion over the rebuilding of Wembley Stadium.
NEW YORK (Odds to win: 20-1)
New York's unsurpassed profile and multicultural population are powerful selling points.
And the prospect of regenerating the city after the 11 September terrorist attacks would give an NY Games added impetus.
Direct US involvement inevitably makes the task of marketing the Games easier.
New York has failed to secure funding for its Olympic stadium, which could scupper the bid before the final vote.
And its evaluation report identified other issues which could worry IOC members.
Vancouver's successful bid for the 2010 Winter Games was a big blow, as the IOC is less likely to back consecutive events in one continent.
The Atlanta Games in 1996 were much criticised, with former IOC chief Juan Antonio Samaranch significantly omitting his usual sign-off that they had been the "best-ever Games".
On a wider front, criticism of American foreign policy could count against New York.
MADRID (Odds to win: 12-1)
Madrid received a solid evaluation report, with its transport system, plans for an environmentally friendly Games and record of promoting Paralympic sport praised.
It has 83% of venues in place or in the pipeline, and its public support rating of 91% is the highest of the five rivals.
The city's status as a major European capital and reputation as a centre of sporting passion will endear it to the IOC - and it has never hosted the Games.
The major factor counting against Madrid is Barcelona's hosting of the Games in 1992.
In Olympic terms, 20 years may be too short a period in which to award the event to the same country, although US cities Los Angeles and Atlanta hosted the Games in 1984 and 1996.
The IOC inspectors said Madrid would need to revise its athletes' village plans, and did not have enough hotel rooms close to its Olympic venues.
MOSCOW (Odds to win: 66-1)
Having hosted the Olympics in 1980, Russia believes it has the knowhow to stage the event and would just need to modernise its sports infrastructure.
All of the sports, including football and sailing, could be held within one city, fulfilling the IOC's wish that a modern Games should be compact.
The bid relies largely on existing venues, and has the backing of President Vladimir Putin.
Moscow's slim hopes faded even further when it received the weakest evaluation report.
Inspectors said it had not supplied detailed information about its plans, and voiced concerns about the quality of hotels.
Given the strength of the rival bids, winning over IOC members will be an uphill struggle.