Starting from the reconstruction of the debate that began at the turn of the last century, the essay reconstructs the main sociological interpretations of the mass incarceration processes that have affected the United States and the main European countries in recent decades. The essay highlights the need to take the prison out of the technical domain of criminology and criminal politics, and to place it at the center of political sociology and civic action. Moreover, it suggests the relevance of qualitative research in prison, when placed within a critical analysis of the political context and social structure in which the prison is immersed.
Keywords: Prison sociology; Mass incarceration.