The research concerned the determinants of social competencies, which are significant indicators of the quality of interpersonal relations. The aim of the study was to verify the connection between social competencies and temperamental traits. The respondent group included 220 university students of different faculties aged 19-24. Social competencies were measured with the use of a Social Competencies Questionnaire by Anna Matczak, while temperamental traits were measured with The Formal Characteristics of Behaviour-Temperament Inventory, by Bogdan Zawadzki and Jan Strelau. The research (...) proved that activity, emotional reactivity and sensory sensitivity are significant predictors of social competencies. The predictive value of these traits differs depending on the kind of measured competency. (shrink)