Peter Piot was a freshly minted doctor, still working toward his PhD in microbiology, when he co-discovered Ebola virus. The experience launched him on a successful career in global health, including a 12-year stint as Executive Director of UNAIDS until 2008. More recently, he was appointed director of the London School of Hygiene and Tropical Medicine (LSHTM), where he is due to start next month. Speaking with Asher Mullard, he discusses the world's failed pledge to deliver universal access to AIDS treatments by 2010, the advances that have nevertheless been made and the changing paradigm of AIDS programs.