Follow-up and monitoring of postoperative patients with rectal cancer is similar to that for colon cancer, with the addition of proctoscopic examination of the anastomosis to detect local recurrence in patients who have undergone low anterior resection (LAR). The prognosis for local recurrence at the anastomosis is much better than for local recurrence elsewhere in the pelvis, but the optimal timing for monitoring the rectal anastomosis is not known, and there are no specific data on whether soft or hard proctoscopy should be used for monitoring. The value of routine endoscopic ultrasound as a means of early surveillance remains unclear. Surveillance after radical colorectal cancer allows evaluation of treatment-related complications, detection of recurrent metastatic lesions that can be radically resected, and detection of early non-infiltrating multiple primary tumors of heterochronous origin. The advantages of closer follow-up and monitoring of patients with stage II or III disease after surgery have been demonstrated in several prospective studies and in three recent meta-analyses, the latter randomized controlled trials comparing low-intensity and high-intensity postoperative follow-up monitoring programs. Additional recent studies that have influenced postoperative surveillance follow-up programs for colorectal cancer include a meta-analysis that included a large sample of 20,898 cases from 18 trials of adjuvant colon cancer, which showed that 80% of tumor recurrences occurred within the first 3 years after radical surgical resection of the primary tumor, and another population-based report that showed that the rates of surgical resection for local recurrence or distant metastases of colorectal cancer and survival rates are increasing, thus supporting closer postoperative follow-up and monitoring in these patients. However, the optimal surveillance strategy after potentially curative colorectal cancer remains controversial.