SUMMARYThe incidence of Staphylococcus aureus in the nose, throat and superficial wound infections of 99 office staff, 129 psychiatry staff and 115 surgical staff was studied over a 4-week period with the purpose of assessing the potential risk to hospital personnel of staphylococcal infection. Incidence rates, both average and cumulative, were essentially similar in the three groups but certain differences in the ecology of the staphylococcal phage groups were observed. Surgical staff appeared to have a more labile pattern of carriage. As in other Scandinavian studies throat carriage rates were high. Staphylococcal carriage seems largely to depend on individual characteristics rather than environmental factors.