Background: The purpose of this article is to draw attention to a significant role of social approval variable in the qustionnairebased diagnosis of drivers' psychological aptitude. Material and Methods: Three questionnaires were used: Formal Characteristics of Behavior - Temperament Inventory (FCB-TI), Eysenck Personality Questionnaire (EPQ-R(S) and Impulsiveness Questionnaire (Impulsiveness, Venturesomeness, Empathy - IVE). Three groups of drivers were analyzed: professional "without crashes" (N = 46), nonprofessional "without crashes" (N = 75), and nonprofessional "with crashes" (N = 75). Results: Nonprofessional drivers "without crashes" significantly stood up against other drivers. Their personality profile, indicating a significantly utmost perseveration, emotional reactivity, neuroticism, impulsiveness and the lowest endurance did not fit in to the requirements to be met by drivers. The driver safety profile was characteristic of professional drivers (the lowest level of perseveration, impulsiveness and neuroticism and the highest level of endurance). Similar profile occurred among nonprofessional drivers - the offenders of road crashes. Compared to the nonprofessional "without crashes" group, professional drivers and offenders of road crashes were also characterized by a significantly higher score on the Lie scale, determining the need for social approval. This is likely to result from the study procedure according to which the result of professional drivers testing had an impact on a possible continuity of their job and that of nonprofessional drivers "with crashes" decided about possible recovery of the driving license. Conclusions: The variable of social approval can be a significant artifact in the study of psychological drivers' testing and reduce the reliability of the results of questionnaire methods. Med Pr 2014;65(3):373–385