<p>This study is an investigation of the level of information people have about the possible causes of mental illness. More specifically, popular concepts about the causes of mental illness are studied. The need for this kind of study is evident when it is considered that any preventive action program should be based on the knowledge people have about problems of mental illness and their possible causes. The results obtained suggest, in general, a high level of information, although a tendency to confuse precipitating factors with etiologi­cal causes was evident. The results also indicate the need to investigate popular concepts about the causes of mental illness with reference to the different mean­ings these concepts can have for different individuals.</p>