The conventional medical treatment of IBD consists of aminosalicylates, corticosteroids, immunosuppressive drugs (azathioprine, 6-mercaptopurin, methotrexate, cyclosporin) and antibiotics. The only drugs able to modify the disease course are azathioprine, its metabolite 6-mercaptopurin and methotrexate. However, these drugs have a slow onset of action and are associated with important side-effects in some patients, necessitating the discontinuation of the drug. Moreover, up to 60% of patients do not respond to these drugs long-term. Fortunately, the management of IBD has entered a new era in the beginning of the 1990s with the development of new biological therapies, selectively blocking the inflammatory cascade. The novel molecules have arisen from the increasing knowledge about the disease pathogenesis and their production has been precipitated by the techniques of molecular biology. Infliximab, the first available biological for Crohn's disease has certainly revolutionised standard treatment. Because of its profound clinical, endoscopic and histological effects, the standard step up approach in the treatment of IBD has been challenged. A large array of new rationally designed biologicals, with a better safety profile and equally selectively acting is underway, and is likely to change our current practise even more dramatically in the next decade.