Warner C. Greene, director of the Gladstone Institute of Virology and Immunology in San Francisco, has been awarded the distinction of American Association for the Advancement of Science Fellow. Election as a Fellow of AAAS is an honor bestowed upon members by their peers. Greene was named a fellow in light of his research on the molecular basis for HIV and HTLV-I retroviral pathogenesis--specifically his efforts to unravel the mechanisms of CD4-cell activation via the normal immune response or viral infection. Under Greene's direction, the Gladstone Institute of Virology and Immunology has established an international reputation for excellence in the study of HIV and AIDS. Greene also serves as codirector of the federally funded Gladstone Center for AIDS Research at the University of California, San Francisco, and is a professor of medicine, microbiology, and immunology at UCSF. The rank of AAAS Fellow was bestowed on 308 scientists and researchers this year. Greene will receive a certificate and pin at the Fellows Forum on February 19 during the 2005 AAAS annual meeting in Washington, D.C.