Results of a clinicopathologic study in 3 cases of nigrostriatal degeneration associated with olivopontocerebellar atrophy are reported. The clinical picture was primarily that of parkinsonism but associated disorders were atypical: sphincter and deglutition disorders, pyramidal signs and action myoclonia; paralysis of vertical gaze (with a deficit of convergence in 1 case) and a cerebellar syndrome in 2 cases; postural hypotension with an invariable pulse, amyotrophy of the hands and a paradoxical response to Dopa: worsening of akineto-hypertonic symptomatology and deglutition disorders in 1 case. Pathologic examination showed similar lesions in the 3 cases: atrophy with pigmentation of the putamen and changes in the substantia nigra, associated with evidence of olivopontocerebellar degeneration. There was marked loss of neurones in the intermediolateral tract in the cord of the patient with the Shy and Drager's syndrome. All cases reported of this abiotrophic association have been of a sporadic nature. The predominance of females, the age of onset and duration of the disease are features that do not differ much from those of pure nigrostriatal degenerative disorders. These cases cannot therefore be considered as a pathological entity but as a particular form of degeneration affecting multiple systems.