The severely mangled extremity presents a challenge in appropriate surgical management. Very few objective data were found about this problem. To clarify the situation, criteria for a "mangled extremity' were defined, a multidisciplined approach employed, and a retrospective graduated grading system developed. Sixty consecutive trauma patients with severely injured extremities during the past 3 years were reviewed. Seventeen patients fit the category of Mangled Extremity Syndrome (M.E.S.). Injuries were retrospectively classified using a graduated grading system directed at four major tissue systems of the extremity involved (integument, nerve, artery, and bone). Additional scoring items were included to define the significance of trauma sustained outside the extremities. Patients who ultimately came to amputation could have been identified preoperatively at initial emergency evaluation utilizing this graduated grading system. Retrospective data suggest that a Mangled Extremity Syndrome Index (M.E.S.I.) of 20 is the dividing line below which functional limb salvage can be expected and above which limb salvage is improbable. Prospective application of this system, as well as an organized multidisciplined approach, could be useful in the identification of functionally retrievable versus probably irretrievable extremities, thus identifying and helping define the indications for amputation. The grading system criteria and results in these 17 patients form the basis of this report.