Evaluations of sexually transmitted infection (STI) programmes often ignore the series of hurdles that patients have to overcome before they are cured. So they tend to overestimate cure rates. Research by the London School of Hygiene and Tropical Medicine, the Institute of Tropical Medicine, Antwerp, the National Institute for Medical Research and the African Medical and Research Foundation, Tanzania, attempted a more accurate estimate of STI programme success in Mwanza Region, Tanzania.