The brachialis is the prime mover for elbow flexion and is innervated by the musculocutaneous nerve. Injury to the musculocutaneous nerve can result in loss of elbow flexion, which is considered one of the most important components of arm function. The flexor carpi radialis (FCR) or flexor digitorum superficialis (FDS) branch of the median nerve to the brachialis branch of the musculocutaneous nerve transfer is considered a reliable surgical reconstruction option to recover elbow flexion. Limited outcome data is available on this nerve transfer in isolation; however, when done as part of the double fascicular nerve transfer, outcomes are good to excellent. Postoperative therapy follows the three-phased donor activation focused rehabilitation approach. Monthly manual muscle testing guides the advancement of motor reeducation and aids the therapist in tracking and achieving desired outcomes for the patient. Throughout the recovery process, the focus of treatment includes donor activation (FCR and/or FDS) to power the brachialis and achieve elbow flexion. Pairing the donor muscle(s) action with passive, active-assisted, and ultimately active recipient elbow flexion is demonstrated and advanced accordingly. Trace activation of this transfer can be seen at around 5 months, and functional movement starts between 10 and 12 months post-surgery.