The authors studied the diagnostic and prognostic value of laryngeal electromyography (LEMG) in adults with unilateral vocal fold palsy. The study included 61 patients who were tested on average seven months after their palsy (4-11 months). In most cases the cause was iatrogenic (51.9%) or idiopathic (26.9%). There was a neural type of tracing in 85.3% of patients, a normal trace in 13.1% and a myogenic type in 1.6%. Only 38 patients completed the designed follow-up. Within this population, 33 patients had a neurogenic type tracing and of these 19 (57.9%) recovered within a mean interval of nine months. Fifteen patients with reinnervation potentials recovered whereas the nine patients without reinnervation potentials did not recover at all. LEMG can differentiate between neurogenic affection and an isolated ankylosis if the immobility is associated with a normal tracing. However, it cannot diagnose mixed lesions. It may offer a prognosis in cases with absent reinnervation potentials suggesting the possibility of an early medialisation.