Summary o 1. In March, 1958, the incidence of respiratory illness in a R.A.F. boys' school was four times that expected, owing to simultaneous outbreaks of streptococcal and adenovirus infections. 2. The streptococcal infection was at first mainly prevalent in a group of older boys. The adenovirus incidence was highest in the new boys. 3. The clinical character of the adenovirus illness appeared to differ from those previously reported in R.A.F. recruits and civilian residential schools, but the significance of this is doubtful. 4. It is concluded that despite previous observations, adenovirus infections cannot be disregarded as a potential cause of high respiratory morbidity in boy entrants at times.