Catatonia is a syndrome of motor dysregulation (mutism, peculiar postures, repetitive speech, negativism, and imitative movements), and is found in as many as 10% of acutely ill psychiatric inpatients. Although its classification has been controversial, the identification of catatonia is not difficult, but it is often missed, leading to the false notion that the syndrome is rare. Catatonia has various presentations, and may be caused by many neurologic and general medical conditions, most commonly mood disorder. Treatments are well defined, and when used, catatonia has an excellent prognosis. This book, by two leading neuropsychiatrists, describes the features of catatonia, teaches the reader how to identify and treat the syndrome successfully, and describes its neurobiology. Patient vignettes from the authors' practices, and many from the classical literature, illustrate the principles of diagnosing and treating patients with catatonia. It is an essential clinical reference for psychiatrists and neurologists.