The Implementation Toolkit of the OECD Principles on Urban Policy aims to facilitate and accelerate the uptake of the OECD Principles on Urban Policy (2019) as a driver of policy reform and improvement in diverse urban policy contexts. It consists of two interlinked and complementary components. First, a self-assessment framework provides governments with a user-friendly four-step guide and a series of questions and indicators to assess the state of play of their urban policy frameworks (“what”), and operational mechanisms (“how”) as well as the outcomes. Second, a policy database offers a selection of 60+ leading examples from around the globe on how national and subnational governments are using the OECD Principles on Urban Policy on the ground to reshape their urban policy. Against the backdrop of current challenges surrounding cities, the Toolkit seeks to support national and subnational governments in making cities fit to face current and future shocks and opportunities.