Cluttering is a globally recognized communication disorder, yet it is often poorly understood. This book presents a historical overview of the efforts of pioneers in the field to demystify the cluttering disorder, before introducing the etiology and symptoms of cluttering from several perspectives: physiological, psycho-linguistic, neurological, social, affective, and cognitive. It also provides an in-depth discussion of the identification, differential diagnosis, and assessment of cluttering, using current and advanced diagnostic procedures before explaining the rationales and unique, innovative procedures for evidence-based treatments of cluttering. Engaging practical examples and theory boxes are featured throughout the book. Providing effective and user-friendly procedures for cluttering diagnosis and intervention, this book is an essential read for all current and future speech and language therapists.