ENThe main aim of this dissertation is to explain why political participation in post-communist societies is so much lower than in Western democracies, considering social trust as a stimulus for political engagement. The empirical puzzle of the research draws from the observations that since its democratization in the early 1990s, the post-communist region has experienced a dramatic decline of both participation in electoral politics and social movements. The lack of civic and political engagement in post-communist countries is perceived as one of the hardships of democratic development in the region. Although formal institutions in the post-communist region are displaying attributes of consolidated democracies, citizens generally feel distant from political life, and are unaware of political decisions and means to influence politics. Admitting that an institutional approach does not provide a full answer to the question why citizens feel detached from politics in post-communist societies, theorists often recoil on cultural arguments. The cultural-based approach derives from the deeper reflections on the communist past and the continuity of both social and personal memories. This dissertation suggests that low levels of political participation in post-communist democracies result from low levels of social trust, which was heavily ruined during the communist regime and right after its collapse. Social trust in this research is considered as both explanandum (chapter 3) and explanans (chapter 2). In the theoretical framework laid out in chapter 2, first, social trust is defined as generalized impersonal trust in other people, including strangers, whom a truster is not necessarily familiar with. The notion of generalized trust stands in contrast with particularized trust, or trust inside specific groups. Social trust generally it refers to trust in the citizenry as a whole.Second, social trust is regarded as an independent variable of political participation. Social capital theories argue that social trust sustains a cooperative social climate, civic norms and a regard for public interests. Thus, social trust is conceived to be conducive to democracy. More specifically, referring to a wide scholarship of social capital and political/civic culture, socially trusting people are more prone to participate in public affairs. This study differentiates between three forms of political participation, namely, voting, party politics (conventional, other than voting) and movement (non-conventional) participation. It is also presupposed that social trust has not only direct positive effects on political involvement, but also leads to political efficacy, which in turn stimulates individuals to embark on political actions. In other words, my assumption is that social resources (social trust) translate into political resources (political efficacy). This dissertation distinguishes between external and internal political efficacy. External efficacy expresses the feeling that “my voice is heard” by the government, while internal efficacy is the conviction that I am skilled enough to influence politics. Social trust enhances political efficacy in a way that socially trusting people more likely acquire political knowledge and information in general about the subjects to be acted on and the methods to employ such actions. Moreover, social trust empowers citizens politically, as they believe that institutions we deal with are fair and people we trust are going to behave by the rules.In chapter 3, social trust is scrutinized as a dependent variable. Using a comparative historical approach, this dissertation considers the development of social trust in post-communist societies. More particularly, this chapter discusses how communist legacies affected the essence of trust and, moreover, how social trust developed in the period of democratic transition after the collapse of the Soviet Union. The chapter explains how communism and the democratic transition had a formidable negative impact on trust, as well as on the abilities of citizens to cooperate for a common good. First, communism deterred individuals from participating in organizations by making this form of participation obligatory. The notion of volunteering as such was discredited. Second, civic and political involvement falls short because of the post-communist disappointment. The economic hardships and efforts invested in “insuring basic survival” leaves no room and no motivation for civic engagement. Third, due to oppressive government, political censorship and harsh economic conditions, post-communist citizens are used to spending their time in family and friendship-based networks instead of spreading their contacts outside these circles. The legacy of spending time within close-knit networks accurately characterizes the contemporary postcommunist society. In turn, as an effect of a vicious circle, since citizens are not being keen on expanding their social contacts with strangers, they lack to opportunities to increase social trust.