Predominant psychopathology in a selected population group--adolescents and young adults at school--in a developing country, is described. The highly selective referral to services was supplemented by active case finding in the community over three years. There were 54 cases of somaticised anxiety (brain fag); 22 cases of depressive neurosis characterised by hypochondriasis, cognitive complaints, and culturally determined paranoid ideation; 23 cases of 'hysteria' in the form of dissociative states, pseudoseizures and fugues; and 39 cases of brief reactive psychosis which differed from the dissociative states more in duration and intensity than in form. There was a temporal relationship between transient psychosis and the school calendar. Anxiety or depression often predated the florid psychotic reaction which served as a form of help-seeking behaviour or defence in intolerable stress.