This dissertation brings together four articles that have been written over a several years and use a range of quantitative data and methods to explore questions about the determinants and effects of social exclusion. An overarching conceptual framework is also formulated in an outline paper. The individual articles are placed in this framework and the contents are reflected upon. For this purpose, the current state of research is consulted in each case in order to obtain an updated assessment of the relevance of the research question and the methods used. The individual contributions draw on different theoretical considerations, which predominantly refer to stress-theoretical approaches, which in turn are to be made fruitful for the analysis of feelings of belonging or exclusion and their consequences for psychological well-being. The work can therefore contribute to analytical-empirical research on exclusion.