This chapter provides a test of the hypotheses on impoverishment and social exclusion. In 1995, with the publication of the Dutch government’s report on poverty and social exclusion, both concepts have found their way in the political debate. The concept of impoverishment may be used to denote the process leading to income poverty, while the concept of social exclusion can be used to refer to a process bringing about a situation called relative deprivation. While the results on the stability of income poverty and relative deprivation are largely based on the log-linear analysis of transition tables, structural models were used to analyze the interrelationship of impoverishment and social exclusion. The survey data used for Belgium are from the Socio-Economic Panel and were collected by the Centre for Social Policy in Antwerp. In Belgium, poverty appears to have increased slightly according to the European poverty line, but to have diminished according to the other poverty lines.