This study reports the findings of a longitudinal study of psychological disturbance in the affected population of Sri Lanka after the 1978 cyclone. The degree of unpreparedness for such a disaster appeared to elicit early appearance of symptoms while group cohesion & feelings of community delayed symptoms in others. Morbidity–including suicidal ideation–continued to affect over half the population one year later. The authors recommend early intervention after such disasters. (6 ref.) (NBB)