Length of time elapsed between recurrent laryngeal nerve (RLN) injury and surgery may affect voice result. The purpose of this study was to compare voice outcome after thyroplasty in patients with short- and long-term vocal fold immobility. Thirty-five patients with longstanding vocal fold immobility (8.3 years) and 35 patients more acutely denervated (10 months) underwent type I thyroplasty. Trained listeners before and after surgery rated perceptual judgments of voice. Acoustic and aerodynamic data were analyzed. Voice outcome did not differentiate the two groups with respect to objective measures. Perceptual ratings of post-operative voice quality favored the short-term patients, with the long-term group having a mildly 'constricted' quality. Thyroplasty yields a functional voice result even when substantial time has elapsed. Patients with chronic immobility may be unable to release longstanding hyperfunctional voicing behaviors even after surgery has afforded them an improved mechanism. In five of 35 long-term patients, therapy enhanced voice quality.