The current book represents an elaborated study of the etiology and pathophysiology of Parkinson's disease, which is a complex neurological disorder. In this book, the ecological and biological agents which become the cause of Parkinson's disease have been described in detail. Other than genetic aspects, pathophysiological aspects of the disease have also been explained. Written by teachers of well reputed academic institutions the book highlights both primary and clinical approaches of Parkinson's disease. This book will be of great use for scientists and researchers. Also, neuroscience students and readers can gain ample knowledge from this book.