The investigators propose to understand the role of lumbosacral spinal cord epidural stimulation (scES) in recovery of autonomic nervous system function, voluntary movement, and standing in individuals with severe spinal cord injury (SCI). Thirty-six individuals with severe SCI who have cardiovascular and respiratory dysfunction and who are unable to voluntarily move the legs or stand will receive scES for cardiovascular function, voluntary movement, or standing with and/or without weight-bearing standing. Training will consist of practicing voluntary movements or standing in the presence of specific scES configurations designed for the voluntary movements of the legs and trunk (Vol-scES), or epidural stimulation configurations specific for standing (Stand-scES). Specific configurations epidural stimulation for cardiovascular function (CV-scES) will be provided during sitting and supine and during maneuvers of orthostatic or cardiovascular stress. The ability to move voluntarily, stand, as well as cardiovascular, respiratory, bladder, bowel and sexual function will be assessed in these individuals with chronic severe spinal cord injury. Quality of life and costs of health care also will be assessed.