Compared with various common neoplasms, there is no national or international agreed clinicopathological staging system for colorectal cancer. Before such a system can be developed, however, there has to be agreement on the methods used for assessment. The Colorectal Subcommittee of the United Kingdom Co-ordinating Committee on Cancer Research has, through its working party on staging, agreed various recommendations as to how the clinical and pathological assessment of patients with colorectal cancer can be standardized. By applying these standardized criteria, patients undergoing surgery can be divided into those having curative or non-curative operations, or operations which are indeterminate for cure. These recommendations represent the first step in ensuring uniformity in the classification of patients with colorectal cancer.