Land use planning policies are a critical component of the institutional architecture that frames housing policy. A core goal of land use planning is to ensure an ‘adequate supply’ of housing. Drawing on planning principles and land economics, the chapter first examines the ways that land use planning measures, such as ‘inclusionary zoning’, can generate affordable housing and the generic arguments for such measures. Second, it identifies features of Australia’s land use planning system that have direct implications for supporting affordable housing and discusses germane planning reforms recently occurring across the country, but especially in New South Wales and Victoria. The chapter then explains and critiques popular claims that Australia’s land use planning regimes are a major cause of housing unaffordability. As part of this consideration, it reviews the controversy around the asserted impacts of Auckland’s 2016 planning reforms which have become a ‘cause célèbre’ in these debates.