There are many classifications of spinal cord injury. The anatomic definitions help in understanding the pathophysiology but are less useful in calculating recovery. Basic classifications, such as those by Guttman and Frankel, are useful for epidemiological studies, especially if one wishes to compare patients internationally or to compare data bases but this information, except in complete lesions, is too limited to allow more refined calculations as to the effectiveness of treatment modalities, especially in partial lesions. An accurate motor index, such as we have described, or such as the Yale index (2), is needed for more specific calculations of recovery if any prediction about the efficacy of various treatments are to be made. We have described our data from the mid-1970s in detail to explain our current treatment protocols. While nothing can be done for the completely paralyzed patient, our treatment of the acute (transiently concussed) near complete lesion and partial lesion must be tailored to maximize recovery. The fact that patients with initially complete motor lesion show some motor recovery in 15% indicates that some lesions are reversible and that we should try to learn to identify these patients and treat them to maximize their recovery. Certain severe partial lesions show poor recovery; we must improve therapy for these patients. Patients with partial lesions and 25-30% motor power below the injury have an 80% (+/- 20%) recovery; we should strive to attain and improve on these good results by appropriate medical and surgical management. In sharing with you our methods and data, we have provided these preliminary conclusions which influence our behavior as neurosurgeons, but it is equally clear that much work still needs to be done. This chapter should represent a reference source with which we can continue to work.