Colorectal cancer is the third most common cancer in the Western hemisphere and the incidence increases with increasing age. Most colorectal cancers are localized with or without lymph node metastases. Up to 20% of patients present with metastatic disease, most commonly to the liver. Surgery is the only curative therapy for localized colorectal cancer and adjuvant chemotherapy is usually recommended for patients with lymph node metastases. Surgery, radiation therapy and chemotherapy are the key components of rectal cancer therapy. Selected patients with recurrent and metastatic disease can be salvaged with surgery but chemotherapy remains the mainstay of therapy for advanced colorectal cancer. Substantial progress has been observed in the treatment of metastatic colorectal cancer in recent years.