There are three areas that we think are just "incandescent". The first is the discovery that certain subsets of CD4+ T cells are more susceptible than others during the non-pathogenic SIV infection of sooty mangabeys. This discovery led us to formulate the highly innovative hypothesis that, in AIDS pathogenesis, it doesn't really matter how much virus is present in the body, or how many cells are killed by the virus, but rather what cells are infected (i.e., where the virus comes from). The second "hot" area is the discovery that CD8+ T lymphocytes, who are potentially the most effective immune cells against HIV and SIV, may reduce virus replication not just by directly killing the infected cells, but also by producing soluble factors that inhibit virus replication. Further defining what these factors are might have major implications for AIDS vaccine design. The third "hot" area is the recent discovery that a minor subset of HIV-infected individuals have learned to adapt to the infection in the same way of the African monkeys that remain healthy upon SIV infection. Understanding the mechanisms beyond this adaptation may lead to advances in how HIV infection is treated.