Next week, some 15,000 delegates will converge on Bangkok, Thailand, for the XV International AIDS Conference. It is appropriate, given the meeting's location in a fast-developing country that has done much to protect its citizens from HIV, that its theme is ‘access for all’. For the poor countries hit hardest by AIDS, this is the crucial issue — they need access to lifesaving drugs, to interventions that can limit the spread of HIV, and to the money to pay for it all.

At the last international conference, in Barcelona in 2002, hopes were high that the rich world would begin to provide the cash to allow developing nations, particularly those in sub-Saharan Africa, to fight back against HIV. “Bangkok will be a time of accountability,” observed Peter Piot, executive director of UNAIDS, the Joint United Nations Programme on HIV/AIDS (see Nature 418, 115; 200210.1038/418115a). Now it is time to take stock.

Credit: C. HUGHES/PANOS

Today's balance sheet reveals a mixed picture. On the plus side, more people than ever before are being treated with cocktails of antiretroviral drugs. According to UNAIDS, 230,000 AIDS patients in developing countries were getting these drugs at the end of 2001; two years later, this figure had risen to 400,000. Price reductions have driven this progress — negotiations by philanthropic organizations have helped to lower costs from a minimum of US$300 per person, per year in 2002 to today's figure of $140.

But across the developing world, the number of patients requiring antiretroviral drugs outstrips provision by at least a factor of ten. To redress that imbalance, there is an urgent need to cut the cost of drugs that can be used when the virus develops resistance to first-line treatments, and to develop simple and cheap blood tests to check whether treatment is actually working. There is also a shortfall in the manufacture of single-pill combined-drug treatments at doses suitable for children.

By 2007, according to UNAIDS estimates, annual global spending on AIDS prevention and treatment will have to rise to $20 billion per year if the developing world's needs are to be met. Currently, the figure stands at just $5 billion. At least the trend is positive, with global spending having increased from $3 billion in 2002. This is partly thanks to the emergence of the Bill and Melinda Gates Foundation as a major player in global health, and the establishment of the Global Fund to Fight AIDS, Tuberculosis and Malaria by the G8 club of rich nations.

The Global Fund, in particular, has been instrumental in convincing poor nations to establish national AIDS treatment programmes. And on 30 June, its board approved grants that should put 932,000 people on antiretroviral treatment. But overall funding is still not assured — currently, pledges from rich nations for 2005 are running at just a quarter of the $3.3 billion forecast.

In the following pages, Nature previews the Bangkok meeting by placing the latest UNAIDS statistics on the HIV pandemic in context (page 134), and profiling a campaigning Thai scientist who is at the forefront of efforts to bring affordable drugs to the African patients who need them most (page 136).

That includes African women who, unable to demand that their sexual partners use condoms, are succumbing disproportionately to HIV. On page 138, we consider whether microbicidal creams or gels could provide them with a degree of protection.

This is just one of the many issues that will keep the halls and corridors buzzing in Bangkok. The long-term dream is still an effective AIDS vaccine. But in its continuing absence, the priority for delegates in Bangkok should be to follow through on Piot's 2002 call to hold the rich world to account. We now have the tools to start bringing the HIV pandemic under control, but this won't be achieved through empty pledges.