High-voltage electrical injury is a rare yet destructive class of burn injury that persists as a serious public health issue. High-voltage exposure is commonly associated with complex wounds to the upper extremities, which can be a significant challenge for burn and plastic surgeons to reconstruct. This intensive and multistage reconstructive process is especially difficult in the growing child. Maximizing upper extremity function is a top priority, as it can have a significant impact on a patient’s quality of life. Therefore, this retrospective review describes lessons learned during a 13-year experience at a specialized pediatric burn hospital with reconstruction of the upper extremity after severe high-voltage injury in 37 children. We found that adherence to the following principles can help promote meaningful functional recovery. These include: (1) frequent assessment during early acute care for the evolving need of decompression or amputation, (2) serial surgical debridement that follows a tissue-sparing technique, (3) wound closure by skin grafting or use of flaps (particularly groin or abdominal pedicled flaps) when deep musculoskeletal structures are involved, (4) early multidisciplinary intervention for contracture prevention and management including physical and occupational therapy, splinting, and fixation, (5) secondary reconstruction that focuses on the simplest possible techniques to repair chronic skin defects such as laser therapy, local tissue rearrangements, and skin grafting, (6) complex secondary reconstruction to address deeper tissue contractures or tendon and peripheral nerve deficits, and (7) amputation with preservation of growth plates, soft tissue transfer, and long-term prosthetic management when limb salvage is unlikely.