contributed to this report for the 80th Congress of the Union Sociale in 2019. It focuses on issues that are fundamental to the HLM Movement. It also includes contributions from Bruno Cautrès, Laurent Davezies, Hervé le Bras, Christine Leconte, Bernard Stiegler, Laurence Tubiana, and Jean Viard. It brings together demographic, political, economic, geographical, philosophical, sociological, environmental, and architectural perspectives.