Complications in bariatric surgery are varied; they are severe at times but infrequent. They may be surgical or non-surgical, and may occur early or late. The goal of this systematic review is to inform and help the attending physician, the emergency physician and the non-bariatric surgeon who may be called upon to manage surgical complications that arise after adjustable gastric band (AGB), sleeve gastrectomy (SG), or gastric bypass (GBP). Data from evidence-based medicine were extracted from the literature by a review of the Medline database and also of the most recent recommendations of the learned societies implicated. The main complications were classified for each intervention, and a distinction was made between early and late complications. Early complications after AGB include prosthetic slippage or perforation; SG can be complicated early by staple line leak or fistula, and BPG by fistula, stenosis and postoperative hemorrhage. Delayed complications of AGB include intragastric migration of the prosthesis, late prosthetic slippage and infection, while SG can be complicated by gastro-esophageal reflux, and BPG by anastomotic ulcer and internal hernia. The analysis of available data allowed us to develop decisional algorithms for the management of each of these complications.