We reviewed the clinical and laboratory findings of 200 patients in Curitiba, Southern Brazil (25 degrees 25'40" S; 49 degrees 16'23" W-GR), with multiple sclerosis (MS)according to Poser's criteria. The patients were classified as: clinically definite (A1 and A2) - 142 patients (71%); laboratory-supported definite - 42 patients (21%); and clinically probable - 16 patients (8%). Relapsing-remitting (RR) form was the most common clinical presentation, with 182 (91%), followed by primary progressive (PP)(16 cases, 8%), and only 2 cases with secondarily progressive form (SP). Nine women and 7 men totalized the 16 PP cases. The mean age of onset was 32.0+/-9.9 (median 32 years). The gender ratio was female 1.8:1 male. All patients, except 3 African-Brazilian, were white. Seven (3.5%) patients developed a clinical history of Devic's syndrome. The initial clinical picture included brainstem/cerebellar syndrome in 126 (63%) cases, sensorial findings in 106 (53%)patients, motor (pyramidal) syndrome in 102 (49.5%), and optic neuritis in 79 (39.5%) cases. 122 (61%) patients had a final EDSS score < 3.5; 45 (22.5%) a score between 3.5 and 5.5, and 33 (16.5%) a score > or = 6.0. There was no significant correlation between the number of relapses or duration of disease with EDSS scores (Spearman's test). Only 14 (7%) of the total number presented the benign form (EDSS< 3.5 after 10 years of disease). We observed a later age of onset and initial clinical findings with higher frequency of brainstem/cerebellar syndrome and optic neuritis, when compared to other Brazilian and Western series