Anti-NMDAR (N-methyl-d-aspartate receptor) encephalitis is a novel autoimmune and paraneoplastic disease often presenting as acute psychosis. Few studies exist in the psychiatric literature on neuroimmunity and behavioral management. This article reviews the epidemiology, diagnosis, pathophysiology, and management of this disease from a neuropsychiatric perspective. Patients have potential for near-complete recovery with early diagnosis and intervention. In addition to immune-suppression and tumor removal, electroconvulsive therapy may be an important tool in treatment of the underlying process in cases developing life-threatening catatonia. Psychiatrists should be familiar with treatment options, since they may be consulted within the context of a multispecialty team.