Unless the diagnostic interviews penetrate to the main issues of the patient's history and illness, the psycho-analyst will be working without knowing what he is required to correct. A clear perspective is not easily obtained once treatment has started. Therefore the author sets out his schema for case-history taking. Information from the interview is grouped under three headings: Anamnestic data, conscious attitudes, and unconscious associative material. It is impossible to summarize this long schema further. Information from other sources is not to be despised, especially with disturbed patients and youthful patients whose parents will feel rejected unless interviewed. Regular reformulations should take place, usually in discussion with the patient.