Everybody in the Sri Lankan capital, Colombo, knows all about "CHOGM" - pronounced "choggum". They speak with enthusiasm, resignation or indignation about the fact that the event is taking place here. The streets are garlanded with banners welcoming CHOGM delegates, and the face of the president, Mahinda Rajapaksa.
Inside the tranquil tropical gardens of the Bandaranaike Memorial Conference Hall journalists and delegates scurry back and forth from venue to venue, with a clutch of events ahead of the main summit that opens today, with Prince Charles representing the Queen, as Head of the Commonwealth.
For Rajapaksa and his government, it is obviously a privilege to be hosting CHOGM - a surprising choice, by any measure, given the country's dismal human rights track record, including disappearances, war crimes and what a UN report described as "a grave assault on the entire regime of international law".
Rajapaksa wants to ensure that the Sri Lankan government comes out of this with reputation enhanced. As one slogan proclaims, Rajapaksa "won the country" (with the defeat of the Tamil Tigers in a most bloody end to the long civil war in 2009), and now he can "win the world".
In terms of enhancing the country's reputation, you might say that Rajapaksa and his colleagues are not doing a great job. In the lead-up to CHOGM, the UN special rapporteur on the independence of the judiciary was among those refused entry to the country. Channel 4 - which worked closely with Amnesty International on producing the powerful, game-changing Killing Fields and No Fire Zone films on Sri Lanka - was blocked by a "spontaneous" demonstration from travelling to the north. This week, relatives of the disappeared, who wanted to come from the largely Tamil north to Colombo for a peaceful "human rights festival" behind closed doors were turned back - because they "might cause a breach of the peace". Partly violent counter-protests, by contrast, were allowed to go ahead with no problems.
For Amnesty International, the summit provides a powerful opportunity to ensure that the human rights voice is heard. The good news is that journalists want to hear what Amnesty has to say. And diplomats, too, are interested in our findings - even if they do not always act on them.
Under the spreading banyan trees in the old town of Galle, after a speech by the president, I got a chance to speak briefly to the Commonwealth secretary-general, Kamlesh Sharma - though not necessarily to convince him that the policy of quiet engagement is not delivering, which is how Amnesty International sees it.
Beyond media interviews and diplomatic lobbying, I have spent much of my time in meetings with some of Sri Lanka's extraordinarily brave human rights defenders - Sinhala and Tamil alike - who talking calmly about the threats against them even as they insist on the necessity of continuing the work.
An Amnesty International petition gained more than 200,000 signatures, demanding truth and accountability, so urgently needed for all sides. Those global demands have helped strengthen the backbone of those governments which are wavering when confronted with the familiar question: do they do the right thing, or the comfortable thing? Canada has boycotted. The UK has promised to bring strong messages. South Africa has sent mixed messages so far (more emphasis on truth is needed). And Australia: well, let's not go there. Prime Minister Tony Abbott seems ready, because of domestic considerations on refugee policy, to use the phrase "not lecturing" as an excuse to remain completely silent on violations.
The Sri Lankans I speak to are grateful for Amnesty International's longterm engagement on the cause of human rights in Sri Lanka.
There is little likelihood of a rosy ending to this story by the end of CHOGM. But the pressures will continue: the UN Human Rights Council meets again in March, with a resolution critical of Sri Lanka likely to be on the table. With enough energy from around the world, that may include achieving an international inquiry. And if that is achieved, it will be a human rights victory to be proud of.