Among 124 patients with meningococcal infections between 1966-1976, 108 had meningitis with a fatality rate of 7.4%, and 16 septicaemia with 18.8% fatality. High risk patients (more than 3 prognostically unfavourable characteristics) increased from 3.5% 1966-1970 to 15.6% 1971-1976, and the total mortality from 3.6 to 10.4%. The most unfavourable prognostic factor was low blood pressure at admission. High risk patients were more common among those who had meningococci with complete or partial sulfonamide resistance (25.7%) than among those having sensitive meningococci (11.9%). When the meningococci were at least partially sulfonamide-resistant, initial therapy with the combination of benzylpenicillin, sulfaisodimidine and chloramphenicol seemed to be more successful than benzylpenicillin alone in patients above 10 years. Ampicillin was used only in children, and these all survived.