Laparoscopic ultrasonographic staging was compared prospectively with conventional computed tomography (CT) and ultrasonographic staging of 24 lower-third oesophageal tumours and 20 gastric malignancies. Following laparoscopic ultrasonography, seven patients regarded as being resectable after conventional imaging were excluded from surgical exploration because of ascites with peritoneal deposits (four patients), liver metastases (one), advanced local disease (one) and poor tolerance of general anaesthesia (one). Preoperative T and N stages were compared with the pathological staging following resection in 34 patients. Laparoscopic ultrasonography was significantly more accurate than conventional CT and ultrasonography in assessment of the primary tumour (91 versus 64 per cent, P< 0·01) and nodal status (91 versus 62 per cent, P<0·05). The addition of laparoscopic ultrasonography to conventional procedures for staging upper gastrointestinal malignancy improved the overall accuracy of staging. Although this may have future implications for the selection of patients for multimodality treatment, management decisions are currently based on laparoscopic findings, which in this study resulted in a resection rate of 97 per cent.