HIV/AIDS treatment information provision involves working with large amounts of changing information from a range of sources. Developing accessible and meaningful information resources that speak to the diverse health communication needs of people living with HIV/AIDS (PHAs) and their caregivers is complex and challenging. This paper discusses evaluation research that assesses the context, effectiveness and impact of a community-based model developed by the Canadian AIDS Treatment Information Exchange (CATIE). CATIE is a bilingual, non-profit organization committed to improving the health and quality of life of PHAs in Canada through treatment information. This paper analyzes data from six studies undertaken from 2002-2003, including key informant interviews (program outcomes; needs and issues) (2003); and user surveys (Web site; workshops; treatment publications; membership) (2002-2003). Aggregate results demonstrate that CATIE has achieved several key outcomes related to individual and community health. Fur thermore, they illustrate the following elements of success: community-based action (PHA involvement, peer-based programs, community capacity development); high quality information (unbiased information from trustworthy sources); accessibility (multiple formats, targeting diverse audiences, providing context through personal stories); adult education approach (skills development, plain language information, respecting choice); and a & quot;determinants of health & quot; approach ( & quot;treatment & quot; includes medical treatments, quality of life, complementary therapies, etc.). A community-based model is a successful approach to providing treatment information to PHAs and their caregivers. This model may help inform development of best practices in HIV/AIDS information exchange/services and HIV/AIDS librarianship.