The figures tell shocking stories of abuse and betrayal -- the sexual exploitation by adults of young human beings.
The lack of political action speaks volumes more.
Among high school and university students in Sri Lanka, 20 per cent of men and 12 per cent of women said they had been sexually abused as children.
In the United States, one in five children who regularly use the Internet receives sexual propositions from strangers. The number of new sex-abuse victims each year tops 100,000.
In Cambodia, nearly one-third of more than 6,100 sex workers interviewed were aged 12 to 17.
The numbers, taken from studies quoted this week in a report from the United Nations Children's Fund, are enough to shock most governments. They also are largely unchanged -- and in some places worse -- than in 1996, when the world's governments set out for the first time to end the commercial sexual exploitation of children.
Five years after the Stockholm congress, an international meeting is to be held next week in Yokohama, Japan, to renew a commitment to fight the child sex trade and to see why so many countries are dragging their feet.
"We still don't see a whole lot of progress, or even a way to tell whether there's been progress," said Lisa Wolff, director of education for development and advocacy at the Canadian branch of Unicef.
Child-rights advocates say that in the last five years there has been a sharp rise in the number of women under 18 sold to pimps -- sometimes by their families and often across borders -- and forced to work as prostitutes.
Sex trafficking ranks third, after arms-smuggling and drug-running, among activities of global organized-crime networks, Ms. Wolff said.
When the congress starts Monday, Canada will be among the many Western countries criticized for not cracking down on the international sex trade involving children. A much-touted Canadian law to battle sex tourism, in which men from affluent countries visit poor nations for cheap sex with prepubescent children or teenagers, has shown little success.
There have been no prosecutions under a 1997 Criminal Code amendment allowing Canadians who engage in sex with children abroad to be brought to trial.
The law requires the consent of the country where an alleged offence occurs. Costa Rica last year refused to give it in the case of an Alberta teacher who was accused of fondling a 17-year-old girl during a field trip.
Ottawa has also rebuffed activists who want to raise the legal age of sexual consent from the present 14, arguing that it makes Canada a haven for child pornographers and pimps running teen prostitution rings.
"The difficulty is, we fix one thing . . . and then another thing happens," said Ethel Blondin-Andrew, the federal secretary of state for children's issues who will lead Canada's delegation to the congress.
She said Ottawa has concluded it cannot implement the kind of national action plan called for in Stockholm because most child-welfare issues fall under provincial jurisdiction.
But Mark-Erik Hecht, senior legal counsel for the child-advocacy group Beyond Borders, said Ottawa should be able to work with provinces and territories to set national goals and meet them.
"How committed are we if we won't do that? " he asked.
The Unicef report, Profiting from Abuse, tells the story of young Nigerian women lured from their homes with the promise of easy money, passed through chains of middlemen and forced to sell their bodies in Italy.