Based on recent epidemiologic evidence, AIDS in older persons (ages 55-79) in Maryland appears to be increasingly contracted heterosexually, particularly in women. Little is known about sexual practices or beliefs about HIV in older persons living in high HIV prevalence urban populations. The purpose of this study was to assess sexual practices, particularly high risk behavior, modifications of behavior including condom use, and perceptions of risk. A behavioral survey, containing 41 potential responses, was developed through modification of The National AIDS Behavioral Survey, focusing on heterosexual activity. The survey was administered to a convenience sample of 55 to 79 year olds attending the Union Memorial Hospital medical clinic. Sexual activity is common within the older population, especially among men. Multiple partners is not unusual in older men. Condoms are commonly used. Older individuals typically are aware of HIV heterosexual transmission risk and a proportion have modified sexual behavior because of perceived risks.