Background: Anastomotic leaks are the major postoperative complications mainly due to technical difficulties. The aim was to review anastomotic techniques and risk factors for leak development. Methods: A Pubmed search was perfomed using the terms esophagogastric/esophagojejunal anastomosis, gastrojejunostomy, gastric bypass, esophagectomy, anastomotic leak/risk factors, gastrectomy, TEA, fluid management, early enteral feeding and reinforcement. English and German literature sources were included with the accent on recent prospective randomized controlled trials (pRCT) with high numbers of cases as well as meta-analyses. Conclusions: There is not enough evidence to recommend either hand sewn or mechanical anastomoses. Surgical skills and routine as well as precise work are necessary to reduce complications. Although stapling leads to uniformity of anastomoses it cannot compensate for surgical deficits. [ABSTRACT FROM AUTHOR]