Advances (from 2004 to 2006) in the use of conventional agents include the molecular mechanisms of action, which have implications for monitoring (azathioprine and thioguanosine triphosphate) and chemoprevention (mesalamine and peroxisome proliferator activated receptor gamma). Advances in biotherapy include new data on monoclonal antibodies (infliximab in ulcerative colitis, adalimumab, certolizumab pegol, fontolizumab, selective anti-adhesion molecules, and others), antisense oligonucleotides, the development of small molecules, and cell-gene therapy (including helminth ova, leukocytapheresis, stem cell transplantation, and probiotic intestinal mucosal delivery systems). However, management of inflammatory bowel disease is about more than drug therapy, dose, and timing. The goals remain induction of remission, limitation of side effects, modification of the pattern of disease, and avoidance of complications. With the cost and complexity of biotherapy, inflammatory bowel disease is emerging as a specific subspecialty.