In an effort to accelerate the regulatory approval of novel anti-HIV drugs, surrogate markers are being used in place of clinical endpoints. These markers can be used to identify pharmacological effects or to predict the possible future benefit of new approaches to therapy. The limitations of using surrogate markers, and the views of 2 senior regulatory experts representing Europe and the US, were discussed at a recent Management Forum meeting entitled ‘The Development of Antiviral Drugs’ [London, UK; October 1994].