Prostitutes, unionists, activists, academics and legislators from around the world gathered at City University for the one-day meeting to share ideas and give advice on how to fight for the rights of women - and men - in the sex industry. The conference was organised by the university's department of applied social studies and Zi Teng, a sex-worker concern group.

"Zi Teng thinks sex work is work. It's no different from any another job," said Yim Yuet-lin, a Zi Teng staff worker. "We don't need criminal law to control the sex industry."

The day-long conference featured speakers from Australia, New Zealand, Britain, the US, Cambodia, the mainland and Taiwan and attracted nearly 100 participants.

Ms Yim said the aim of the conference was to show local participants how other countries had reformed their laws to improve the lives of sex workers. While prostitution in Hong Kong is not illegal, soliciting is.

She said other laws also existed that unfairly discriminated against prostitutes and allowed police to abuse their powers.

These included the requirement of having a licence to provide a massage between the neck and the knees, which had led to police going undercover to "investigate" but not make arrests. Instead, they enjoyed free sex, Ms Yim said. Kate Dickie, of the New Zealand Prostitutes Collective, told the story of the fight for decriminalisation in that country. In June last year, 60 members of parliament voted for it and 59 against.

"There is prostitution in every country," Ms Dickie told the gathering. "Changing the law is a huge accomplishment." Now it was possible, for example, to report physical abuse to the police and get fellow workers to act as witnesses without fear of getting into trouble, she said.

Sitting in the audience was Stephen, part of a group working with male prostitutes on the mainland. Stephen, who is from Shanghai and did not want to give his full name, said sex workers in China were stigmatised, as were gays. "Male sex workers are doubly stigmatised," he said, adding that male prostitutes on the mainland suffered great shame.