Colorectal cancer is one of the most common cancers worldwide. Through well-designed clinical trials, advances have been made in the treatment of localised and advanced colorectal cancer. It has been established that 6 months of 5-fluorouracil-based chemotherapy will improve overall survival in patients with stage III colon cancer. The role of adjuvant chemotherapy in stage II colon cancer remains an unresolved issue. Recent studies have demonstrated an improved survival with the addition of irinotecan to 5-fluorouracil and leucovorin for the treatment of advanced colorectal cancer. Immunotherapy, molecular targeted therapy and liver-directed therapy, in addition to new chemotherapy combinations, are all being evaluated for the treatment of localised and advanced colorectal cancer. Ongoing and proposed studies are incorporating the identification of genetic and molecular abnormalities, which may provide prognostic information as well as direct treatment decisions.