Based on a representative survey among the members of German and Austrian associations of relatives of mentally ill people, this paper examines the beliefs commonly held by relatives of persons suffering from schizophrenia concerning the causes of this disorder. A comparison of the information gathered in the course of this survey with the results of a representative survey conducted among the general public in Germany shows that relatives will usually look to biological factors when searching for the cause of schizophrenia, while the general public tends to cite psychosocial factors, especially stress-related factors, in order to explain the development of this illness. We attribute this discrepancy to relatives' greater exposure to the knowledge of psychiatric experts as well as their having to deal with their own feelings of guilt.