Virology Experts in the Boundary Zone 153 2008). Despite criticism of his role in the controversy, Goudsmit kept his position at the AMC; and when three years later Science announced him as Europe's most important HIV/Aids researcher (Cohen 1993 ) the Buck-Goudsmit affair was not mentioned at all. During the second interview Goudsmit described his 1980s self as a hubristic expert (Goudsmit 19 May 2008) , and other sources support that view: someone who is very confident about his knowledge base. This stage of his career involves frequent loss of control over statements and quotes: being tempted by journalists to utter sweeping statements and daring analyses. Analysing the interviews with Goudsmit, we find two interrelated problems for the hubristic expert. The first is a lack of experience in controlling the media; the second is a lack of knowledge of the limits to his expertise. As we will see, a gradual shift in both these aspects later in his career would change his role.