STD prevention programs promote practices and messages that are presumed to fit with most conditions of U.S. communities. Yet, the social and cultural contexts for low-income ethnic communities may frame STD prevention differently, so that people calculate their risk and take actions based on what they have learned through their own observations and life experiences. To understand how people at high risk for STDs make decisions and take actions to protect themselves from these diseases, the authors conducted 38 ethnographic interviews with individuals living in arural community in the South. Practices they reported include selecting "safe" partners on the basis of appearance, familiarity, or church attendance; washing before and after sex to prevent infection; self-treatment with antibiotics obtained without a prescription; and visiting the clinic frequently for checkups for asymptomatic infections. The authors compare and contrast their worldview with the public health concepts of primary and secondary STD prevention.