The OK Condom campaign uses advertisements like this to put condoms where they are needed.

"Make every night OK, with OK," the slogan goes, part of a new initiative to continue Cambodia's fight against HIV and AIDS.

The slogan was included in the speeches of prominent guests at an event last week, an occasion for a campaign more like advertising.

The OK Condom campaign marks a different approach to the fight against the disease, at a time when Cambodia's sexual mores are in flux, and as more and more of the populace are youths.

The lights were turned down, and the event appeared more like a night in a bar or karaoke club, two of the main targets of the campaign, which hopes to put condoms that sell three for 500 riel in the hands of young people who need them.

"It's too dark to read," a jovial Mam Bunheng, the health minister, said as he prepared to deliver a speech.

When the lights came up a bit, the minister told a story, of how he once asked a woman about HIV and condoms.

"Do you know how HIV-AIDS is transmitted?" he asked. "The lady responded: 'Eh, uncle, you don't you watch TV, listen to the radio, or read the newspaper, do you? AIDS is transmitted by sexual intercourse. It's easy to avoid it. Just don't have sex; then how can you transmit it?"

The minister, who announced he was 60 years old, laughed before asking participants to consider the woman's response: "Brothers and sisters, help me think about this. AIDS comes from sexual intercourse. Just stop having sex to avoid HIV? I'm afraid we could not endure without it, could we?" He laughed some more.

Putting aside the abstinence option, he said he had not tried OK Condoms yet—but he would. He hoped OK would be better than other brands, and he made an appeal for loyalty in romance, one to one.

"You students, you should try not to have a sex partner, or, if you have many partners, well we have a stratagem—our friend, OK."

Even in Phnom Penh, it is difficult to find young men or women who will discuss their sex lives openly. Side-stepping the issue, Yin Chakrya, a 19-year-old student, said she knew condoms prevented unwanted pregnancy and that could help with a family's living conditions. She said that before she marries, she would have her fiancé tested three times before agreeing.

Young men won't wear condoms, she said, because they believe their girlfriends are loyal to them. But even if a woman is loyal, if her partner has many other partners, he could transmit "the killer," she said.

"As far as I know, most students—boys—don't use condoms because of the feeling of trust," she said. "But they could not know the trust sometimes is only an appearance that can be faked."

Citing the experiences of friends with boyfriends, she said, "If she was to use a condom, he said, 'Don't you love me, and don't trust me, darling? What kind of sweethearts have we been?'"

Yin Chakrya then appealed to girls not to soften their stance when boys ply them with words. One of her friends was infected with HIV from a boyfriend, she said, who hid his knowledge about the disease until she had become pregnant. The baby was aborted, and the mother was HIV positive, Yin Chakrya said.

OK Condoms will be marketed to the young, and to the poor. They will sell at half the price of No. 1 Condoms, which were widely distributed to brothels and sex workers in the past. No. 1 will remain a free condom for those who can't afford them at all.

Other targets of the OK campaign will remain the same, sex workers and clients, men who have sex with men, drug addicts, and those who are already HIV positive. They will marketed as protection against the disease, but also against pregnancy, as high numbers of children can put a strain on a family.

Meanwhile, the affluent remain at risk for HIV, as much as five times greater, thanks to a habit of drinking outside the home, which can lead to unsafe sex practices, he said.

Piper Campbell, deputy chief of mission at the US Embassy, said for the past 15 years, through PSI, the US and the UK had sponsored programs that reduced the highest prevalence of people living with HIV from 2 percent in 1998 to 0.9 percent in 2006.

The US has funded programs worth more than $120 million to support the fight against AIDS, according to an embassy statement. As of Monday, the OK Condom campaign will be one of these.

San Sophal, a condom vendor from Kampong Thom province, said he expected the condom would sell better than No. 1, because those who buy the latter are perceived to be about to visit brothels. The OK Condoms will be better received, he said.

"Some buyers are shy to buy condoms," he said. "They will buy OK Condoms only."