The ultimate tensile strength of newly apposed tissue is the sum of the strength of the physical construct holding the tissues and the strength of biologic healing. For successful laparotomy closure or incisional hernia repair, the total strength of the repair must remain greater than the opposing forces applied at the suture tissue interface. We discuss the key biologic and physical elements that must be considered with abdominal wall closure including biologic wound healing, suture material the foreign body reaction (FBR), and the forces that contribute to either failure or success of repair. Given limited progress over recent years, recent research focuses on an improved distribution of forces at the suture/tissue interface (STI) that can limit tissue tearing, suture pull-through, and incisional hernia formation.