Objective: To assess the safety and effectiveness of long-term use of functional electrical stimulation (FES) for exercise, standing, and walking in individuals with paraplegia, using percutaneous intramuscular wire electrodes. Design: Case study with more than 17 years of follow-up. Setting: Institutional rehabilitation practice. Study Participants: Two long-term (17 years) volunteer participants with paraplegia who were able to stand and walk using FES. Intervention: Chronically indwelling percutaneous intramuscular wire electrodes connected to a portable microprocessor-controlled stimulator were used to exercise muscles while controlling trunk, hips, knees, and ankles and develop activation patterns to produce standing and walking. Main Outcome Measures: Clinical complications, electrode performance and survival probability, and functional performance. Results: The most noted clinical complications included localized inflammation at the electrode site and superficial infection that responded well to topical and oral antibiotic treatment. The change from coil-wire electrodes, with a survival of 35% after 1 year, to double-helix electrodes improved electrode survival to 80% at 1 year and 48% at 5 years. Maintenance of the multichannel percutaneous FES walking system required replacement of an average of 2 electrodes every 6 months. Participants were able to use their system for independent exercise and standing and for walking with standby assistance. Conclusion: Although the FES system was devised as a temporary means of achieving functional activation until permanent means could be achieved, it was found to be effective and relatively safe for more than 17 years. Two long-time users of the system had no adverse effects to their skeletal system. The most common problems were daily care of electrodes at exit sites, frequent irritation of the skin around electrodes, and replacement of failed electrodes. The percutaneous system has the potential for short-term rehabilitation in individuals with incomplete paraplegia or stroke.