Introductory audiology is an essential and fundamental aspect of the education of all students who are interested in the two related professions of speech-language pathology and audiology. This book is primarily intended to serve as a comprehensive introductory text for students who are preparing to enter both of these fields. As such, it tries to address the needs of at least two rather different groups of students. Those planning a career in audiology need a broad overview of the field and a firm understanding of its many basic principles so that they have a solid foundation for the future as doctors of audiology in clinical practice.