OBJECTIVE: To evaluate the impact of a single-shot preoperative antimicrobial prophylaxis (AMP) to reduce the rate of Surgical Site Infections (SSIs) in a rural sub-Saharan hospital. SUMMARY BACKGROUND DATA: We analyzed the incidence of SSIs in a rural Tanzanian hospital with very limited resources and found that AMP was administered after incision in 88% without covering the expected pathogens. Inadequacy and mistiming of AMP proved to be major risk factors for SSI in this study. Subsequently, 21.6% of patients developed an SSI after clean or clean-contaminated surgery, with 60% of detected pathogens being resistant to the administered antibiotics. In developed countries, preoperative single shot AMP is widely used and effective in the prevention of SSI. METHODS: Implementation and monitoring of guidelines for routine and adequate single shot AMP within 2 hours prior to incision in every clean and clean-contaminated intervention. RESULTS: In the preintervention group, 527 patients qualified for routine AMP that was administered in 88% of patients after incision and did not cover the expected pathogens to a large extent.114 patients (21.6%) developed an SSI, with 60% of detected pathogens being resistant to the administered antibiotics. After implementation of the guidelines, the incidence of SSIs significantly decreased from 21.6% to 4% (11/276). CONCLUSIONS: The implementation of a single shot AMP dramatically decreased the rate of SSI in a hospital with very limited resources. Such guidelines, developed by industrialized countries, are even more effective in non-industrialized countries.