The aim of this paper is a comprehensive overview of theoretical concepts of social support representing the background for the empirical studies that are presented further on. The paper follows the basic steps of research proceduresin the social sciences. Definitions of social support are presented first, followed by the operationalization of its basic dimensions and the presentation of the most frequently used models of social support. The main effects model, the buffering model, the perceived and the received support models, the model of social integration and the model of social support as transactional process are presented. In the final part, social support is related to egocentered social networks.