There is both scientific and clinical evidence that individuals with voice disorders benefit from the services of speech language pathologists. This evidence is documented in experimental research, clinical reports, retrospective analyses, and case studies. This paper reviews the literature on the effectiveness of behavioral treatment for voice disorders primarily using studies published in peer-reviewed journals. Data are reviewed that support voice treatment applied to various disorders including those related to vocal misuse and hyperfunction, special medical or physical conditions, and psychogenic factors. Directions for future research are suggested to maximize clinical and scientific outcomes and to enhance knowledge on the efficacy of voice treatment.