These are the first Games in which all participating nations will include women athletes. But the road to gender equality is a long one.
Olympics chief lauds London as first gender-equal Games
The IOC president Jacques Rogge has asserted that London 2012 is the first Olympic Games at which all delegations include women.
"It is a very important point," Mr Rogge said. "Before this there was no gender equality in sports and gender equality is a human right."
Speaking on the eve of London 2012, he said he was not going to tempt fate just yet by declaring these "the best Games ever" - the habit of his predecessor Juan Antonio Samaranch.
But he showed no such caution on the point of gender equality.
"With Saudi Arabian female athletes joining their fellow female competitors from Qatar and Brunei, it means that every national Olympic committee has sent women to the London 2012 Olympic Games," Mr Rogge said.
But who could really blame him if, in a quiet moment, he might worry that point?
This, after all, is the subject on which Mr Rogge has chosen to stake his name. This is the foundation on which he hopes to build his Olympic legacy - or the rock on which it may founder.
Qatar and Brunei are fielding women for the first time and changes in regulations that allow female athletes to compete covered up have made the once impossible possible.
But the truth is that until Wodjan Shahrkhani and Sarah Attar, the Saudi women named as the first to compete in the Olympics, take their place alongside their competitors nobody can be quite certain that Mr Rogge has succeeded in his aim.
And while he can and has brought pressure to bear on member countries, he cannot compel them to bow to his will.
The IOC's commitment to gender equality in sport was renewed with an updated charter in June, which states that one of the roles of the IOC is to "encourage and support the promotion of women in sport at all levels and in all structures, with a view to implementing the equality of men and women".
Pierre de Coubertin, founder of the first modern Olympic Games in Athens in 1896, banned women from competing entirely on the grounds that their inclusion would be "impractical, uninteresting, unaesthetic and incorrect".
Fans of beach volleyball - who can count Prince Harry as the most high-profile, if least surprising, among their number - might take issue with his notion of aesthetics.
No one could argue that the Olympics have not come a very long way since M de Coubertin's day.
Bit by bit, year on year, the percentage of women's participation has risen from just 2.1 per cent in 1900, when women were restricted to golf and lawn tennis, to a forecast 46.6 per cent in London 2012.
This year will be the first time women's boxing features on the Olympic schedule, with female flyweight, middleweight and lightweight divisions joining the men's events.
Also this year: Afghanistan has one woman among their six Olympians; Bahrain's eight women outnumber their male teammates two to one; Jordan is sending four women in a field of nine athletes; four of Qatar's 12 Olympians are women; and Brunei has one woman in a squad of three.
But even if this year does finally see women included across all countries, true equality is still a way off.
Japan and Australia have been accused of treating their women Olympians as second-class citizens, flying them over in economy while their male peers relaxed in business or first-class seats.
Basketball Australia has vowed to review its travel policy, which stuck the women's team - far more successful than the men's, having won silver medals at the last three Olympics - in economy class on the 23-hour flight.
The Japanese women's football team were relegated to economy on the flight to Europe.
The Japan Football Association argued the men's team merited business class because they were professionals.
The slight provoked an understandably grumpy Homare Sawa, last year's Fifa women's world player of the year, to play one thing few women would ever choose to - the age card.
"It should have been the other way around," Sawa said. "Even just in terms of age we are senior."