Catatonia was first described by Karl Ludwig Kahlbaum in 1874, occurring in association with other psychiatric and medical disorders. However, in the nineteenth century the disorder was incorrectly classified as a subtype of schizophrenia. This misclassification persisted until the publication of DSM-5 in 2013 when important changes were incorporated. Although the etiology is unknown, disrupted gamma-aminobutyric acid has been proposed as the underlying pathophysiological mechanism. Key symptoms can be identified under 3 clinical domains: motor, speech, and behavioral. Benzodiazepines and electroconvulsive therapy are the only known effective treatments. Timely recognition and treatment have important outcome, and sometimes lifesaving, implications.