As part of a longitudinal cohort study in rural Malawi in 2000, 469 men and 758 women were asked to respond to a series of surveys, were tested for gonorrhea and chlamydia, and received their results and treatment, if applicable, for themselves and up to 2 partners if positive for either sexually transmitted infection (STI). Two years later, in 2002, 328 men and 525 women were again asked to respond to survey questions, tested again for gonorrhea and chlamydia, and were also tested for HIV - of these, 247 men and 453 women had also given urine samples in 2000. In 2000, the gonorrhea and chlamydia prevalence was 6.2% and 5.8% among men, and 3.6% and 4.9% among women. Two years later, prevalence of gonorrhea and chlamydia was 0.7% and 1.4% among men, and 1.3% and 1.1% among women. Although we did not test for HIV in the first round, the HIV prevalence in 2002 was 19.2%. The implications of the findings are discussed in the context of interventions for STI prevention and to reduce HIV transmission in sub-Saharan Africa.