Nerve transfer is an essential component of the reconstruction strategy for traumatic brachial plexus injuries. During nerve transfer, a redundant nerve or nerve fascicle is redirected to the distal portion of an injured nerve that has lost innervation. Nerve transfer must be evaluated in the broader context of the patient’s injury pattern and reconstructive options. There are several domains that must be considered carefully when preparing for nerve transfer, including a thorough preoperative evaluation of the injury, timing of reconstruction, suitability of donor nerves, and priorities for functional restoration. In this chapter, we review the indications and objectives for nerve transfer during surgical reconstruction of traumatic brachial plexus injuries in adults. As the indications for nerve transfer continue to grow, it is critical for nerve surgeons to be knowledgeable of the various motor and sensory nerves available for transfer, so that patients have the greatest opportunity for functional recovery.