Abstract
Syringe-exchange programs (SEPs) have proven to prevent the spread of bloodborne pathogens, primarily human immunodeficiency virus (HIV), among injection drug users (IDUs). In the United States, only about 7% of IDUs have access to and use SEPs. Some IDUs engage in secondary syringe exchange (SSE), meaning that one IDU (a "provider") obtains syringes at an SEP to distribute to other IDUs ("recipients"). This formative qualitative research was conducted to understand why and how IDUs engage in SSE to aid in the development of a large-scale peer HIV prevention intervention. Interviews with 47 IDUs in Oakland and Richmond, California, indicated that SSE was embedded in existing social networks, which provided natural opportunities for peer education. SSE providers reported a desire to help other IDUs as their primary motivation, while recipients reported convenience as their primary reason for using SSE. Building SSE into SEP structures can facilitate an effective provision of risk reduction supplies and information to IDUs who do not access SEPs directly.