The Nike Football Training Centre is a billboard of a building in the loud and proud tradition of Soweto, South Africa's biggest and most ambitious township. From the rooftop of the three-story building, you can see an endless fabric of low-rise government housing and ad hoc shacks, but also signs of change: BMWs parked at the Maponya Mall, cabs heading to the revamped taxi stand at Baragwanath Hospital, and worshippers crowding into new Pentecostal churches. On most days, you will find groups of kids at play and in training on the immaculate soccer fields below.

These scenes suggest a new prosperity in Soweto, driven by the Johannesburg municipality's long-overdue investment in its infrastructure and by a burgeoning black middle class. But there is an underlying story, too—a reason for more churches and for upgrading the hospital's taxi facility. Soweto has some of the highest rates of HIV/AIDS infection in a country where the epidemic has lowered life expectancy to less than 50 years, and many of the township's young people engage in risky activities. Some kids on the fields of the Nike Centre hope to be spotted by a scout and make it to the pro leagues, but most come for fun. In the process, they hear messages that may save their lives.