Gastric cancer is the fourth most frequent cancer in the world. For curative treatment and local control of gastric cancer, surgery is essential. The extent of the lymph node dissection is still under debate. Only one available trial showed significantly increased overall survival, whereas in all other randomised trials no significant difference could be found. As surgery alone often is not sufficient in the curative treatment in gastric cancer, different (neo)adjuvant treatment strategies have extensively been studied. The recently published MAGIC trial showed downstaging, downsizing and an improved overall survival for patients treated with perioperative chemotherapy, compared to surgery alone (difference 13%, p = 0.009). The INT 0116 trial on the other hand, demonstrated the benefit of postoperative chemoradiotherapy compared to surgery alone for patients with a curative resection of gastric cancer. However, the quality of resections in this trial was poor, illustrating the importance of standardisation by quality control. This could be done by the Maruyama index, which quantifies the likelihood of unresected disease. In the Netherlands, the CRITICS trial has recently been launched, which will be a quality controlled trial comparing postoperative chemoradiotherapy and chemotherapy on survival and/or locoregional control in patients who receive neoadjuvant chemotherapy followed by a D1+ gastric resection.