The authors, supervising psychiatric residents in an outpatient clinic, frequently found the inexperienced psychotherapist having great difficulties with a well-defined clinical type, the female Don Juan. She is a charming, seductive woman whose history reveals repeated seductive, followed by castrative, behavior with men. This acting out is continued into the treatment situation, the resident being often unaware of his being exploited, manipulated, and defeated in his efforts. Instructive examples are presented in which the supervisor clarifies the situation for the helpless resident, who then is better able to cope with the patient's acting out and really help her.