Comprehensive yet compact and user-friendly, the fourth edition of Introduction to Communication Disorders takes a unique lifespan perspective that enables students to focus both on disorders and also on how these disorders impact on the lives of individuals. Through case studies, technical illustrations, best practices boxes, and other features, each chapter describes a specific disorder, related assessment, and applicable intervention methods – all with a foundation in evidence-based practices. More than a simple catalog of communication disorders, this relaxed and readable introductory text illustrates each chapter with a detailed case study. In addition, the new and completely revised fourth edition of this book has been updated to include new features, new research, and new material. New to this Edition: The addition of evidence-based practice (EBP) throughout the text provides students with the most effective and efficient assessment and intervention practices possible. Research updates and revisions throughout the text, including over 400 new and relevant research studies, keeps the book current and relevant in an ever-changing field. Best practices boxes in each chapter cover the ideal assessment and intervention process for each disorder discussed and offer students a quick and easy-to-read reference. Website references in each chapter allow readers to further explore topics relating to communication disorders on the Internet. New diagrams and figures illustrate the locations of various disorders, especially those with a neurological basis. New communication disorders have been added, including childhood motor speech disorders and other language disorders, making the text more comprehensive. A redesigned companion website is now more user-friendly and better helps students learn the material included in the text and explore additional websites of interest.