To minimize the possibility of developing lethal colorectal cancer (CRC) in ulcerative colitis (UC) and Crohn's colitis, patients are usually enrolled in a program of dysplasia surveillance. The success of a surveillance program depends on the identification of patients with dysplasia and timely referral for colectomy. While a number of issues might stand in the way of a surveillance system achieving its maximal effect (less than ideal agreement in the interpretation of biopsy specimens, sampling error by endoscopists, delays in referral to surgery, and patient drop-out among others), circumstantial evidence supports the concept that colonoscopic dysplasia surveillance is an effective means of reducing CRC mortality and morbidity while minimizing the application of colectomy for cancer prevention. This review critically appraises key issues in the diagnosis and management of dysplasia in UC and Crohn's disease as well as adjunct efforts to prevent CRC in inflammatory bowel disease.