On the billboard is a photo of two crested cranes - Uganda's national bird. "The Crested Crane sticks faithfully to one partner until death. Abstinence and faithfulness - 100% guaranteed," reads the caption below the entangled lovebirds.
By Will Ross
BBC News, Kampala
Read on and you learn that the poster has been put up by the office of first lady Janet Museveni. The first lady's office is one of the major recipients of US funding to combat HIV/Aids.
Has the C for Condom been dropped from Uganda's Aids information campaign?
On the other side of the billboard is a picture of a truck driver passing "Safari Hotel" as two women try to flag him down. "Thank GOD I said NO to Aids - driving home to my wife," it states, before asking: "Abstinence - why not?"
This is a "condomless" billboard. There is no mention of the word "condom" or "safe sex".
This push for abstinence and faithfulness in the fight against HIV/Aids has been welcomed by some sections of society, especially religious groups.
Pastor Martin Ssempa says donor funding has for years been heavily biased towards condom promotion, and he claims this has lead to an escalation in casual sex and infidelity.
The outspoken pastor says it is time for that to change.
"Until recently, all HIV-related billboards were about condoms. Those of us calling for abstinence and faithfulness need billboards too," he says.
However, others consider it dangerous to push the "A" for "Abstinence" and the "B" for "Be Faithful" if the "C" for "Condom" message is lost or diluted.
After all, it was the ABC approach and a policy of openness inspired by President Yoweri Museveni which helped Uganda perform well in the fight against HIV/Aids compared to other countries.
Many African governments have fared miserably in attempting to counter the HIV pandemic, with devastating consequences.
By comparison, Uganda has performed well in bringing down the HIV prevalence to around 6%. In many parts of the country, it was at least three times as high during the early 1990s.
The New York-based group Human Rights Watch (HRW) has strongly criticized the Ugandan government, accusing it of pushing the abstinence line while downplaying the safe sex message.
A "life-threatening" shift which HRW says is orchestrated and funded by the US.
It says the funding for abstinence is due to President George W Bush's conservative Christian views, which are similar to those of Uganda's first lady.
The US says it plans to spend more than $100m combating HIV/Aids in Uganda this year - of which more than $8m will be on the abstinence and faithfulness programme. Some of that money will be focused on the young.
On a wall in Kitante Hill secondary school in Kampala is a poster advertising an abstinence march.
"Please wear your 'True Love Waits' T-Shirt if you have one," the organisers advise.
"Abstinence is the best method. It is 100% safe against early pregnancies, STDs [Sexually Transmitted Diseases] and the common one, HIV, which is very deadly as it has no cure at the moment," says Linda, 19.
There have been concerns about the quality of condoms in Uganda
Alex, 19, tells me he has a girlfriend. "We are in love but we are not going to have sex before marriage."
Sandra, 16, says of her boyfriend: "His friends sometimes give him wacky ideas, but we sit down and talk it out as we both decided not to have sex before marriage."
Sandra says she was inspired by Linda and Alex. "If these guys can abstain, then I can also do the same no matter what pressure I get."
I ask if there are many people at the school who do not take on this abstinence message.
"Oh yes," replies Alex. He leaves the room for two minutes and returns with Dan and Usher, aged 20 and 19.
"I've tried abstinence but it is quite hard," says Dan. "I always walk with condoms in my pocket. But I don't think there is enough education in schools about safe sex."
Usher believes abstinence is a good idea but says it is not realistic: "I think most people get tempted too much and I think condoms are a good alternative."
Despite the funding for abstinence based programmes, the Ugandan government is keen to deny that there has been any shift of emphasis.
"I would like to assure the world that we have continued to maintain abstinence, being faithful and the use of condoms as the principal strategy in the fight against HIV/Aids," says Uganda's Minister for Health, Mike Mukula.
But while US cash has seen the canoodling crested cranes flying onto Uganda's billboards, it seems the birds are somewhat territorial and may have chased other messengers away.
Until a few months ago, a free magazine promoting safe sex was distributed to secondary schools by a non-profit organisation.
But this recently became controversial and faith-based organisations were concerned the magazine was encouraging sex.
As a result, the magazine has been ditched, and that avenue for getting the safe sex message to the students has now gone.
The head of guidance and counselling at Kitante Hill school, Samuel Along, is concerned that the safe sex message is not getting through.
"I have seen students at the school pairing up. They come and talk to me and I begin realising they have sexually transmitted diseases. And if we have been insisting on abstinence, don't you think there is a very good possibility they have not used a condom?"
This is a respectable secondary school in the Ugandan capital where there is good access to information.
But the majority of young Ugandans do not make it beyond primary school and in a country where most people live on less than $1 a day, the link between poverty and sex is strong.
Rogers Kasirye works in the slums of Kampala with street children and teenage prostitutes. Poverty has forced many of them into taking risks.
Christian groups in Uganda and the US are behind the new emphasis
"It is an economic problem. Many of the young people we are working with are surviving on sex, and the only option or barrier they have is the condom."
The Ugandan health ministry has been giving out about 80 million condoms a year, free of charge.
But after recent concern about the quality of the condoms, the ministry is now giving out far less and is sending condoms abroad for testing as it tries to acquire machines for checking condom quality locally.
Whilst churches are pushing the abstinence message, not all religious leaders are happy with President Bush.
Reverend Gideon Byamugisha is HIV-positive and he hopes the US will carefully assess the way in which it influences policy in Uganda.
"We are still hopeful that America, being a strong and well-meaning country, will not go down in history as a country which exported ideas at the expense of people's free will to choose."