This comprehensive text provides the hearing health professional with a broad overview of the advances in technology and clinical insights relating to hearing aid devices and those who use them. Emphasis is given to the most current advances in clinical assessment and hearing instrument technology. In addition to clinical assessment techniques, this text offers detailed analysis of the application of digital signal processing. Psychology is included to help professionals meet clients' emotional as well as acoustic needs. This is a valuable book for academic and clinical professionals involved in the selection and fitting of hearing aid devices for the acoustically impaired