Open abdomen therapy is used in trauma and non-trauma patients where the abdomen is not possible to close, or the intraabdominal conditions is not suitable for closure. In 2007, a new technique that made use of negative pressure wound therapy and mesh-mediated fascial traction for closure of the open abdomen was described from the Department of Surgery in Malmö, Sweden. With this new technique, fascial closure rates were high but long-term incisional hernia formation was seen in approximately half of the patients alive after five years. To overcome the high incisional hernia incidence, a new technique utilizing a permanent on-lay mesh for traction and reinforcement of the incision at fascial closure was developed. The aim of the thesis is to evaluate early and late clinical outcome of the novel vacuum-assisted wound closure and permanent on-lay mesh-mediated fascial traction technique.