It is unclear whether ulcerative colitis (UC) is a progressive disease similar to Crohn's disease (CD). Patients with UC often are undertreated because of the possibility of curative colectomy and the perception that the disease burden is lower than that of CD. We discuss findings from studies that aimed to determine whether UC and CD have the same disease burden and should be treated in the same intensive way. We discuss the similarities between CD and UC, including effects on quality of life, long-term complications, strictures, increased risk of cancer, pseudopolyps, functional abnormalities, and anorectal dysfunction. Contrary to the generally accepted idea, surgery cannot cure UC. Postoperative complications, especially pouchitis and fecal incontinence, affect more than one third of patients. CD and UC each pose substantial economic burdens. Monitoring, treatments, and goals of therapy are similar for all inflammatory bowel diseases. Earlier initiation of disease-modifying drugs might reduce the progression of UC and reduce its burden after surgery, although UC might not cause the irreversible damage observed in patients with CD.