1. A group of experienced psychiatrists interviewed, for 20 minutes each, 886 highly selected officer candidates. On the basis of the information gained in the interview, they estimated the probable success of each candidate in the position of Junior Combat Officer. They also made judgments on each man of his dominant personality type and his typical defense mechanisms utilized.2. The psychiatrists' judgments of probable officer success correlated, at a statistically significant level, with the independent judgments of line officers who made extensive observations of the candidates over a 4-week period. This finding makes tenable the conclusion that the psychiatric interview can be used to identify potential officer leaders in a group of carefully selected, homogeneous, intellectually superior, adult men.3. Data were presented demonstrating that the group of psychiatrists showed significant differences in the frequency with which they observed different personality types in random samples drawn from the 886 men and, also, that different psychiatrists tended to see different personality traits in the same man.4. A tentative hypothesis is offered as the best explanation of the differences reported in the paragraph above. Briefly, this hypothesis states that the differences observed in the diagnostic judgments of psychiatrists result from differing frames of reference which are derived from the transactional life experiences of the psychiatrists. This results in a greater sensitivity on the part of the psychiatrist for certain facets of the patient's personality structure, and a greater perceptual distortion on the part of the psychiatrist to other facets of the patient's personality structure. Once perceived, correctly or distortedly, each item is subjected to the psychiatrist's value system.5. Further tentative tests of the "projection" hypothesis are underway. A study designed to make a more crucial test of the hypothesis will be reported.