Few studies have examined risk-reduction alternatives to consistent condom use for HIV prevention among heterosexual young adults. We used qualitative methodology to explore risk reduction strategies and contextual factors influencing attempts to reduce risk in an urban, high morbidity sexually transmitted infection (STI) clinic. Focus groups were conducted October-December 2014 with heterosexually identified men (n = 13) and women (n = 20) aged 18-29 seeking STI screening at an urban clinic. Groups were audio recorded, transcribed verbatim, and analyzed for thematic content using Atlas.ti software. Quantitative information included sociodemographics, HIV/STI testing history, and 6-month sexual behaviors. Among 33 predominantly African-American participants with a median age of 22, risk-reduction strategies included monogamy agreements, selective condom use with casual and high-risk partners, and frequent HIV/STI testing, though testing was commonly used as a post-hoc reassurance after risk exposure. Many men and women used implicit risk assessment strategies due to mistrust or difficulty communicating. Concurrency was common but rarely discussed within partnerships. Despite attempts to reduce risk, monogamy agreements were often poorly adhered to and not openly discussed. Alcohol and substance use frequently interfered with safer sexual decisions. Participants were aware of HIV/STI risk and commonly practiced risk-reduction strategies, but acknowledged faulty assumptions and poor adherence. This work provides insights into risk-reduction approaches that are already used and may be strengthened as part of effective HIV/STI prevention interventions.