We studied the clinical features, the natural history and disability in 47 progressive supranuclear palsy patients and brain imaging aspects by routinely performed MRI in a subgroup of 25. Unexplained falls together with atypical parkinsonism (symmetric, levodopa unresponsive without resting tremor) are good clinical pointers of the early diagnosis, since they occurred within the first year. Cognitive slowness and unspecific visual complains are also early symptoms, while usual cardinal signs such as supranuclear palsy are more delayed. Blepharospasm and eyelid opening apraxia as well as deep sighs are also quite characteristic clinical features (1/3 of cases). Cardinal signs (falls, pseudobulbar signs, supranuclear gaze palsy) worsened rapidly (20 to 30 months) towards a major disability. In the 20 patients deceased during follow-up, the mean survival time was about 5 years. The MRI study showed typical cortical fronto-temporo-parietal atrophy, mesencephalic and quadrigeminal plate atrophy with third ventricle dilatation. In conclusion, unexplained falls associated with atypical parkinsonism are contributive for the early clinical diagnosis. Non specific visual complains could be useful pointers in the absence of supranuclear ophthalmoplegia. MRI contributes to the clinical diagnosis even in the first 3 years of the disease course.