The concept of underclass in the parliamentary debate 1971-2021. This article is a study of how the concept of underclass has been used in the Swedish parliament during the years 1972-2021. The questions asked are: to whom has the concept been applied, what problems are attributed to the underclass and what consequences are assumed to follow from the existence of an underclass? This is studied by means of a discourse analysis of parliamentary documents, such as motions, committee reports and addresses in which the concept has been used. The analysis shows that the concept of underclass has been used by all parties in the parliament. During the first part of the timeframe, left-wing parties used the concept more frequently, but during the last decades the concept has mostly been used by right-wing parties. Problems ascribed to the underclass are deficient education, unemployment and welfare dependency. Another conclusion is that the concept seems to refer to two different underclasses, an old domestic underclass that is in employment, and a new immigrated underclass that does not work.