The paper aims to reflect on the links between the phenomena of employment and unemployment in a context governed by the intense flexibilization of work and the institutional and normative reconstruction of the patterns of workers' protection. The argument unfolds in three directions. Firstly, it accompanies the movement to redefine the notion of "unemployment," pursuing, with the help of the recent sociological literature, the constitution and social legitimacy of the new phenomenon of the "long-term unemployed." Secondly, it compares theoretical developments that have attempted to understand this phenomenon with the efforts made by the Brazilian labor sociology to interpret the problematics of unemployment. Finally, it argues in favor of the heuristic value of contextualized comparisons to test, for the Brazilian case, the hypotheses developed by the sociology of unemployment in Europe, particularly France.