The management of pancreatic pseudocysts (PPC) has traditionally been surgical. Although highly effective, surgery may be associated with a complication rate of 35 % and a mortality of 10 %. This has encouraged the development of nonsurgical approaches. Percutaneous puncture and aspiration under ultrasonographic or computed tomography (CT) guidance has been used, but aspiration alone has been found to be ineffective, with high recurrence rates of up to 71 %. Continuous percutaneous drainage with indwelling catheters reduces the relapse rates, but may be associated with a complication rate ranging from 5 % to 60 %. Complications include fistula formation, infection, and bleeding. Endoscopic transmural drainage of PPCs is an alternative nonsurgical approach. Since the first reports by Sahel et al. [ 1 ] and Cremer et al. [ 2 ], endoscopic drainage of PPCs has become an established procedure. It entails the creation of a fistulous tract between the PPC and the gastric lumen (cystogastrostomy) or duodenal lumen (cystoduodenostomy). Endoscopic access to the PPC is established, and a nasocystic catheter or a stent is placed for continuous drainage. The obvious limitation of endoscopic transmural drainage of PPC is its relatively “blind” approach. The risk of perforation is particularly high when endoscopically visible intraluminal bulging is absent. A major risk of endoscopic cystoduodenostomy or cystogastrostomy is hemorrhage (6 % of cases) [ 1 ] [ 2 ]. The ideal approach for PPC puncture combines endoscopy with real-time endosonography using an interventional echo endoscope. Several authors have described the use of endoscopic ultrasound (EUS) longitudinal scanners for guidance of transmural punctures [ 3 ] [ 4 ] [ 5 ] and drainage procedures. Using this technique, puncture of cysts under direct endosonographic control is possible even where there is no bulging of the gastric or duodenal wall. This improves the safety of PPC puncture, and increases the number of patients in whom endoscopic transmural drainage is appropriate. In this review, we descibe the different techniques of EUS-guided cystogastrostomy or duodenostomy, and the complications and outcomes of this new technical approach.