This article discusses the personological vs. relational approach to temperament. The first approach, which views temperament as a relatively permanent and cross-situationally consistent disposition, is dominant. The present article presents arguments in favour of broadening the concept of temperament. This newly broadened concept will also include relatively stable determinants of behaviour dynamics specific to certain classes of situations. Moreover, temperament is defined as an element of the system of stimulation regulation. Temperament is viewed as a hypothetical construct. The surplus meaning characteristic of such hypothetical constructs is associated in this case with optimum stimulation as a regulatory standard, and with properties of the system of stimulation regulation. It is also connected with the open question of the degree of differentiation of temperament dimensions.