Research is lacking about what makes or breaks collaboration between researchers and HIV services providers. This study identified factors that influence providers' levels of willingness to collaborate in HIV prevention scientific research. Survey measures were grounded in in-depth interview data and included providers' "willingness to collaborate," and providers' attitudes toward researchers' availability, benefits of research, and agency preparedness. This survey was administered to 141 providers in New York City. A hierarchical regression model showed that providers' perceptions of researchers' availability (p less than 0.05), research benefits (p less than 0.001), and agency preparedness (p less than 0.05) were associated with providers' willingness to engage with researchers to purse HIV prevention research. Findings indicate that researchers need to be socially and professionally available, future HIV research should benefit providers and consumers, and policy makers should help agency settings develop human and financial resources in preparation for research. (Contains 2 tables.)