We surveyed neurologists and chronic care facilities in and near two New Jersey counties with a combined population of 799,022, regarding cases of progressive supranuclear palsy. All suspected cases were examined personally, using rigid criteria. The prevalence ratio was 1.39/100,000. A total of 50 New Jersey cases yielded median intervals to onset of requiring gait assistance, 3.1 years; visual symptoms, 3.9 years; dysarthria, 3.4 years; dysphagia, 4.4 years; requiring wheelchair, 8.2 years; and death, 9.7 years.