The psychological interview is a technique used by psychologists, psychiatrists and psychotherapists for interventions. In people’s opinion, its function is diagnosis of troubles and Freud’s talking cure. It is difficult to assign to the expression psychological interview the value of research that it might have. Anyway, the interview is the technique of election for all those professional figures that expect to draw information from their clients or patients in order to know their psychophysical state, formulate a diagnosis and successively construct a possible modality of intervention. The article focuses on the psychological interview as a technique born to carry on researches, both for diagnoses and therapies.