'Fear of flying' is a convenient expression used in the armed forces to categorize flyers with emotional symptoms sufficient to threaten or impair proficiency in flying. The author presents his observations of fifteen patients with 'fear of flying', referred for psychiatric appraisal during 1953 and early 1954. He expects his findings to prove valuable to civilian and military physicians concerned with the emotional problems of flight. The sequence of reactions typifying 'fear of flight' is rather constant. These stages have their counterpart in the nonpilot. The process of attaining a calm, mature approach to flying in pilots and passengers involves passing through distinct stages during which the mechanism of repression is operative.