Numerous materials have been used over the years for vocal fold augmentation. Early use of bioreactive compounds, such as paraffin, gave way to relatively inert substances, such as Teflon. More recently biocompatible materials, such as collagen and autologous fat, have gained wider acceptance. Autologous fat, in particular, is an easily obtainable source for potential rehabilitation of scarred, paralytic, and atrophic vocal folds. However, long-term systematic follow-up has been lacking. Since 1991 we at the University of Kansas Center for Voice and Swallowing Disorders have employed autologous fat for vocal fold augmentation, primarily for either paralysis or repair of a volume-deficient vocal fold segment. Twenty-two patients have completed > or = 1 year of follow-up studies, including graded video-laryngostroboscopy, electroglottography, computerized acoustic analysis, and blinded perceptual analysis by two speech-language pathologists. Statistically significant improvement was demonstrated in many parameters tested, frequently improving with time. Although the volume-deficient group had more "normal" values, the paralysis group had greater improvement in many variables using fat injection. We conclude that while autologous fat injections of the vocal fold may have long-term benefits, certain technical considerations and criteria of selection of patients are critical for success.