Gastric cancer is one of the most common cancers in the world. The prognosis of the disease is poor, with only 40% of patients eligible to undergo potentially curative surgery. Even for those patients who undergo a complete resection, the rate of recurrence is very high. Extensive studies of multidisciplinary adjuvant treatment have been conducted seeking to improve the cure rates in the past two decades. The benefit of D2 dissection is still controversial and is undergoing prospective evaluation. Preliminary results from the United States Gastrointestinal Intergroup study, a well designed trial, have shown overall survival benefit of postoperative chemoradiation therapy. Neoadjuvant chemotherapy or chemoradiation is under active study in order to increase the number of patients to undergo potential curative surgery. Although many chemotherapy regimens have been developed recently, only modest clinical efficacy has been demonstrated for advanced metastatic disease. So far, there is no single regimen considered to be standard.