The treatment of colorectal cancer severely affects both patients suffering from colorectal cancer and their families. To ensure that the patient is fully informed about the impact of colorectal cancer treatment, members of the oncology care team must present to the patient not only potential treatment benefits, but also negative aspects of treatment, such as frequent physician visits, treatment expense, and frequent side effects. Treatment-related side effects not only decrease the patient's quality of life, they also may compromise treatment efficacy by necessitating dosage reductions or interruptions in therapy. Participation by both the oncology care team and patients is crucial for effective side effect management. Methods to reduce the incidence and severity of side effects associated with standard, commercially available chemotherapies for colorectal cancer (ie, 5-fluorouracil-based regimens and irinotecan [CPT-II, Camptosar; Pharmacia & Upjohn Company, Kalamazoo, MI]) are discussed. Brief information about the side effects and management of side effects associated with selected investigational agents, doxifluridine (UFT, Furtulon; Hoffman La Roche Inc, Nutley, NJ), capecitabine (Ro09-1978, Xeloda; Hoffman La Roche Inc), and 5-ethynyluracil (776C85; Glaxo Wellcome Inc, Research Triangle Park, NC) is also presented.