The NCCN Rectal Cancer Guidelines panel believes that a multidisciplinary approach is necessary for treating patients with colorectal cancer. Patients with T1 or T2 lesions that are node negative by endorectal ultrasound and who meet carefully defined criteria can be managed with a transanal excision. Abdominal peritoneal resection or low anterior resection with total mesorectal excision is appropriate for all other rectal lesions. Either preoperative chemoradiation or postoperative chemoradiotherapy is standard for patients with suspected or proven serosal invasion (pT3) or regional node involvement. Patients with recurrent localized disease should be considered for resection with or without radiotherapy. Chemotherapy regimens using irinotecan or oxaliplatin should be considered for patients with distant metastasis. The panel endorses the concept that treating patients in a clinical trial has priority over standard or accepted therapy.