Facial nerve palsy is one of the most devastating nerve injuries with important functional and psychological impact on the patient's life. However, facial nerve can be reconstructed. When the proximal facial nerve stump is not available, a donor nerve, like the hypoglossus, can be used to neurotise the distal facial nerve stump. Here we present the anatomical and physiological bases of the hypoglossal-facial nerve anastomosis as well as the indications, timing and surgical techniques of this operation