Self-expandable metal stents (SEMS) are well known and established in the therapy of malignant stenosis of the gastrointestinal tract. But they are also used for the treatment of benigne stenosis, fistulas, perforations or bleeding. SEMS are categoried by the material they are made of, the covering, the length, the diameter and other special features like drug-eluting stents, biodegradable stents or thermoplastic stents. The releasing system is differentiated between through the scope systems (TTS) or guide-wire system with fluoroscopy. SEMS are used in the esophagus, the esophago-gastral-junction, the gastric outlet, the duodenum, the bile or pancreatic duct, colon and rectum. Early complications are rare. Stent-migration and occlusion are the main late complication of SEMS.