The serratus anterior muscle protracts the scapula and provides stability for glenohumeral joint motion. It is innervated by the long thoracic nerve (LTN) taking input from cervical roots 5, 6, and 7. Injury to the LTN limits arm elevation and overhead function. The intercostal nerve (ICN) to long thoracic nerve (LTN) transfer has been described as a reconstructive technique to recover scapular stability. Postoperative care includes motor reeducation that is guided by the three phases of the donor activation focused rehabilitation approach (DAFRA). The shoulder is often immobilized in the first month to protect the coaptation and pectoralis major muscle repair, when applicable. Phase 1 includes patient education, passive shoulder/scapular range of motion, and donor activation. Intercostal donor activation is achieved with inhalation, exhalation, coughing, trunk flexion, and trunk rotation. Co-contraction of the donor muscles with passive recipient muscle exercises is emphasized in phase 1. Exercises are advanced based on monthly manual muscle testing results of the serratus anterior muscle. Phase 2 begins with the recovery of active contraction in the recipient muscle, and exercises are advanced to include donor activation with active-assisted serratus function. Patients who recover full scapular protraction will advance to phase 3 for shoulder and scapular strengthening. Functional movement of the serratus anterior muscle may take 18 months, and maximal outcome may ultimately take 2–3 years to achieve.