Crohn's disease (CD) is characterized by transmural inflammatory disease involving any portion of the gastrointestinal tract. Patients with CD have increased mucosal concentrations of the cytokine tumor necrosis factor-alpha (TNF-alpha), a key mediator of mucosal inflammation. In addition, TNF-alpha has multiple biologic activities involved in apoptosis, metabolism, and activation of granulocytes, lymphocytes, eosinophils, fibroblasts, chondrocytes, and endothelial cells. Recently, infliximab has emerged as a novel chimeric monoclonal antibody that inhibits TNF-alpha. Infliximab is indicated for the treatment of moderately to severely active CD in patients having an inadequate response to conventional therapy. To date, a small number of clinical trials with infliximab have demonstrated efficacy and tolerability when the agent is initiated as a 5-mg/kg single intravenous infusion. In patients with fistulizing CD, administration of 2 subsequent 5-mg/kg doses 2 and 6 weeks after the initial dose appears to be efficacious. Infliximab seems to be a promising therapeutic strategy for patients with refractory CD.