William is a virologist with a background in genetics and microbiology. His research interest since the mid-1980s has been largely focused on the AIDS virus, HIV-1: particularly how it replicates in macrophages and how smart nucleic acids can be developed to prevent its replication. He teaches virology to medical students at Oxford University and is a Fellow of Brasenose College. He is also Oxford University’s Pro Vice-Chancellor for Planning and Resource Allocation. William joined the board of Trustees in September 2014.