This report is a continuation of our previous report on chronic spinal cord stimulation in disorders of the motor system. Improved statistics were observed following changing from the early conventional two-electrode system to a newly developed four-electrode system. The success of the four-electrode system lies in the analysis of both the electrode combinations and the frequency of stimulation. These are carried out on each patient and remain the most critical aspect of the technique. The details of the multiple lead system--the technique of implantation and protocols for carrying out electrode and frequency analysis--are presented.