This sub-study provides an opportunity to examine how these community-related themes impact the transmission of HIV and HAART knowledge, attitudes, and behaviors among Vancouver area MSM. Within the context of the recently initiated population-level biomedical intervention represented by the expanded, universal and free of cost HAART access to the MSM population in British Columba, this sub-study aims to better understand the symbiotic relationship between HIV risk and shifting MSM social and sexual networks, as potentially mediated by advances in HIV knowledge and HAART treatment.