Poorly controlled Crohn's disease (CD) often requires surgery for such complications as strictures, fistulas, and abscesses. The goal of postoperative treatment is to suppress or prevent inflammation and maintain mucosal healing. Probiotics, antibiotics, 5-aminosalicylates, immunomodulators, and antibodies to tumor necrosis factor are all used to prevent postoperative recurrence. In this article, recent studies are reviewed. Azathioprine/6-mercaptopurine are moderately effective at preventing and treating postoperative CD, whereas infliximab/adalimumab are highly effective and probiotics and 5-aminosalicylates minimally effective. We base the choice of postoperative medical therapy on the patient's risk profile for postoperative recurrence. Whatever postoperative therapy is used, the mucosa should be assessed within 12 months to determine if the approach is effective. If active inflammation is found, then treatment should be intensified. By treating CD aggressively after a first surgery, future surgeries can be delayed or averted.