Cystogastrostomy or cystojejunostomy at open operation has been the usual treatment for symptomatic pancreatic pseudocyst. The aim of this study was to assess prospectively the results of percutaneous cystogastrostomy (PCG) for the treatment of symptomatic pseudocysts. The technique of PCG comprised initially of drainage of the pseudocyst with a 10 Fr percutaneous, transgastric catheter. This initial drainage catheter had two components; the first, between the pseudocyst and the stomach, drained the pseudocyst and the second, between the stomach and exterior, acted as a percutaneous gastrostomy. The initial drain was left in situ for 14 days, at which time it was exchanged percutaneously for the definitive PCG; a double ended Mallecot type catheter that drained between the pseudocyst and the stomach. The latter catheter was left in situ until there was no residual pseudocyst demonstrated on computerized tomography scan and was removed endoscopically. Eleven patients with large (> 6 cm), symptomatic pseudocysts have been treated with PCG. All patients were treated successfully without the need for surgical intervention. The median time to radiological resolution was 24 days. There were four episodes of sepsis, two related to central venous line infections nad two related to catheter blockage. Percutaneous, cystogastrostomy blockage was managed by either replacing the initial drain or inserting a second catheter. The median follow up after successful treatment was 9 months (range 2-17). There were no symptomatic recurrences and one small (2 cm) asymptomatic recurrent pseudocyst. This preliminary experience with PCG demonstrates the efficacy of this procedure for treating symptomatic pancreatic pseudocysts.