1. We have described what happens to patients a number of years after injury of the sciatic nerve or of its divisions; there were 329 who had been under observation for periods ranging from three to eighteen years. The neurological recovery was recorded in every case and, more important, the behaviour of the limb as appreciated by the patient. 2. Although it was generally true that good neurological recovery and good function went together there were remarkable discrepancies. Isolated paralysis of the medial popliteal or of the lateral popliteal nerve was often compatible with good function, though patients with lateral popliteal paralysis usually needed toe-raising apparatus. Even total sciatic paralysis sometimes gave little trouble. 3. Of the various types of injury, clean wounds and traction lesions led to rather better than average return of function. 4. Some degree of pain was present in about half the cases, and over-response–exaggerated and painful response to an ordinary stimulus–was present in one-third of the cases. 5. Repair of the posterior tibial nerve was rarely worth while; no less than eight out of twelve patients with this type of injury exhibited over-response. 6. One-third of the patients showed vasomotor and trophic disorders: coldness of the affected limb, erythema, thinness or pigmentation of the skin, changes in the nails or oedema. 7. Pressure sores were the most serious consequence of sciatic nerve injury and at some time or other were present in 14 per cent of our patients. The cause was deformity rather than insensibility of the sole. 8. Of the various palliative operations Lambrinudi's tarsal arthrodesis gave such disappointing results that we doubt whether the operation is worth doing. Tenodesis, revived as a time-saving expedient during the war, was a failure. For lateral popliteal paralysis anterior transplantation of tibialis posterior is excellent. 9. Amputation was done in only ten cases. When it was performed for fixed deformity with secondary ulceration the result was satisfactory. When it was done because of pain there was no relief. Amputation is, therefore, avoidable provided that vigorous steps are taken to prevent or correct deformity; it should not be done for the relief of pain.