Progressive supranuclear palsy (PSP) is a rare neurodegenerative disorder in which, classically, patients present with postural instability and falls, parkinsonism, and slowing of vertical saccades. PSP patients typically have deficits in cognitive functioning, difficulties with most daily activities, and present with notable behavioral disturbances-particularly apathy, impulsivity, and irritability. Using data from 154 patients meeting criteria for clinically probable PSP, domain and total scores of the Neuropsychiatric Inventory were examined and compared to demographics, disease severity, cognition, and motor features. Behavioral abnormalities were common in this cohort of PSP patients, with more than half experiencing apathy, depression, and sleeping problems, and approximately one third displaying agitation, irritability, disinhibition, and eating problems. Few clinical correlates of neuropsychiatric symptoms were observed in this cohort. Given the prevalence of neuropsychiatric symptoms in PSP, these patients are expected to be frequently seen by psychiatrists and other mental health professionals for symptom management and increased quality of life. Clinical trials are clearly needed to address the neuropsychiatric morbidity in these patients.