This book is the first attempt at bringing together a volume of work from a range of professionals with an interest in spasticity. The framework for the definition was developed in part by the authors contributing chapters that make up this volume. The book represents the current state-of-the-art regarding definition, measurement, pathophysiology (all state-of-the-art summaries) and simultaneously gives clinicians guidance on clinical management. This work combines coverage of both spasticity and contractures as these two phenomena are often closely interrelated. Current researchers do not differentiate between these individual impairments and, as such, there is significant confusion in the literature. This book discusses both conditions and then separates them into their respective components. If these two conditions co-exist (which is generally the case), then the management of a patient will need to be customized to individual clinical presentations.