Social exclusion can be defined as a practice where individuals are fully or partially excluded from social, economic and cultural networks. Hence, the concept of social exclusion is multidimensional and associated with economic, social, political and cultural aspects. This paper analyses the causes of social exclusion. It specifically explores the reasons why an individual experiences social exclusion today on the assumption that this may lead to similar experiences in the future. Literature suggests that there are two underlying processes that lead to the persistence of social exclusion. One, individuals are heterogeneous in terms of observed and unobserved adverse characteristics which are important for someone to experience social exclusion over time. Second, individuals may experience social exclusion due to state dependency, that is, the experience of social exclusion in one period may itself incite the chances of experiencing it in subsequent periods. Differentiating the two processes is important because policy options for addressing the two social exclusion processes are also different. Using data from the Tanzania National Panel Survey (TZNPS), this paper provides new evidence on the state of social exclusion in Tanzania.