Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases which can be difficult to control with conventional therapies. Thanks to a better knowledge of their physiopathology, new therapies aimed at specific targets of the inflammatory cascade were developed. Three monoclonal anti-TNF antibodies were produced. Infliximab and adalimumab, currently widely used, can induce sustained remission in Crohn's disease. Infliximab is also efficacious in UC. Certolizumab pegol provides good short term results; its long term efficacy, however, remains to be assessed by further clinical trials. Therapies targeting leucocyte trafficking (anti-integrine) have also been provided and are associated with good clinical responses in Crohn's disease. Natalizumab (anti-alpha4) is responsible for significant side effects and is no longer in use in gasrtoenterology in Europe whereas MLN02 (anti-alpha417) has a good profile in terms of efficacy and safety. Monoclonal anti bodies targeting other cytokines are under development, mainly ustekinumab which inhibits IL12 and IL23. Ustekinumab generates favourable clinical responses in Crohn's disease. The development of biologic therapies in inflammatory bowel disease has dramatically altered the course and management of these disorders.