OBJECTIVES: To describe the role and possible contribution of private drugstores in sexually transmitted infection (STI) management in rural Tanzania. METHODS: A cross-sectional study that included drug sellers in private drugstores in eight districts of Tanzania. Data collected through interviews with drug sellers and the simulated client method presenting a male and female STI case. "QATI" scores (Questions, Advice, Treatment and drug Information) were developed to describe overall STI management. RESULTS: Although 74% of drug sellers stated that there were no STI-related drugs in the store, medications were dispensed in 78% of male and 63% of female simulated client visits. The clients were dispensed drugs recommended in the Tanzanian guidelines for syndromic management of urethral or vaginal discharge in 80% of male and 90% of female cases. Drug sellers dispensed antibiotics during 76% of male and 35% of female simulated client visits. Dosage regimens were often incorrect and complete syndromic management rarely provided. Most drug sellers agreed that it is within their professional role to give information on STI treatment (89%) and prevention (95%). Drug-use information was almost always provided. Advice was however seldom given and questions occasionally asked. Overall STI management was better for men than for women. CONCLUSIONS: The drug sellers, although aware of the prescription-only status of antibiotics, saw themselves as having a role in STI management and were ready to provide drugs. In this resource-limited setting, drug sellers could provide effective and safe STI management especially to male patients if given appropriate tools to improve practice. The consequences of this for official policy need to be discussed.