This dissertation analyzes the mechanisms of the French housing market documenting its constraints and the impact of several housing policies. It aims to increase our understanding of the mechanisms at work on this very particular market where land has a key role. The first chapter tries to document the place of land through the past decades. Some economists have been documenting a steady decline of its importance during the XIX and XX centuries. However, such decline was progressively balanced by the sharp appreciation of housing wealth and more particularly its land component. The second chapter tries to understand the origin of this rise in residential land value documenting one of the key parameter of the housing market: the supply elasticity of the French urban areas. This chapter starts defining two different concepts related with the supply elasticity. The first one is the intensive margin supply elasticity and designates the reaction of developers following a short run increase in housing prices. The second one describes how real estate price vary when a city is growing. It shows that French urban areas are less elastic than their US counterparts. The third chapter uses a natural experiment, the Scellier Housing Tax Credit (STC) and shows that it had a limited quantitative impact on the housing production. The fourth chapter documents the crowding out effect of private construction by social housing.