To develop a relevant, community-based prevention campaign, the authors examined, using street-intercept interviews, syphilis-related knowledge, circulation of information, and screening and treatment practices among four hundred residents of two inner-city communities in Houston, Texas, where syphilis case rates exceed city, county, and national averages. Although awareness of syphilis was near universal, one-fourth of the respondents thought syphilis was incurable, and a large proportion confused syphilis with other sexually transmitted diseases (STDs), mentioning discharge and burning or itching in the genital area as symptoms. Almost four out of five respondents were aware of free treatment and screening facilities in the local area, yet, less than two of five expressed the intention to get tested within the next month. Only 22 percent had seen or heard anything about syphilis in the past twelve months. The resultant prevention campaign is discussed along with implications for the development of comprehensive STD prevention and control campaigns in similar poor and underserved communities.