SUMMARYStrains of Neisseria meningitidis isolated from patients with meningitis or septicaemia without meningitis in Scotland during the years 1972-82 have been reviewed together with details of the age, sex, disease and outcome of the patients from whom they were isolated. A total of 1185 strains were isolated, of which 927 were examined at the Meningococcal Reference Laboratory (Scotland): 19-3 % were of serogroup A, 63 % of group B, 9-6 % of group C, 6 % of W135 and 1-6 % of other groups. Non-groupable strains were rare. Disease was most common in the first years of life but there was a difference in the age distribution of disease due to the different serogroups, the proportion of disease due to group B being smaller in adults than that due to other serogroups. The overall mortality in meningitis was 7-5 % and in septicaemia was 20-6 %, although there were differences between the rates for the various serogroups. The serogroup distribution differed in disease as opposed to meningococci isolated from carriers although group B strains were predominant in both series. Overall, approximately 15 % of strains were resistant to sulphadiazine, the proportion of resistant group A strains being higher than that of other serogroups.