The prognosis after surgical treatment of gastric cancer remains poor. This review aims to clarify the indication for multimodal treatment of gastric cancer. A systematic literature research and evaluation of clinical data presented at important international cancer meetings were undertaken. Recently published results of large randomized phase III trials underscore the potential value of neoadjuvant chemotherapy or adjuvant chemoradiotherapy in gastric cancer. However, data from randomized controlled trials are still scarce, and it remains uncertain which subgroups of patients should routinely undergo multimodal treatment. In view of the side effects of pre- and foremost postoperative therapies, a more distinct definition of prognostic and predictive markers is warranted. Neoadjuvant chemotherapy is a rising option in locally advanced gastric cancer. Adjuvant chemoradiation has been shown to be beneficial in gastric cancer patients who have undergone suboptimal surgical resection. The benefits of adjuvant chemotherapy alone seem to be very small.