ABSTRACT This Society for Medicines Research symposium was held on March 6, 2008, at the National Heart and Lung Institute, London, U.K. The meeting, organized by Kate Brown and David Fox reviewed the state-of-the-art in biotherapeutics. This is an area that is acquiring increasing importance in drug discovery and development portfolios, offering new and alternative ways of treating a wide range of conditions as well as opening up new and exciting areas of science and technology. Presentations ranged from the therapeutic potential of monoclonal and polyclonal antibodies, vaccines and oligonucleotides, through to the scientific basis of the emerging area of RNA interference. In addition, some of the technical aspects of delivering novel therapies and ensuring their quality were also discussed.