The notion “risk governance” refers to an integrated concept on how to deal with public risks in general, and so-called complex, ambiguous and uncertain risks in particular. These ideas have been informed by interdisciplinary research drawing from sociological and psychological research on risk, Science and Technology Studies (STS) and research by policy scientists and legal scholars. The notion of risk governance pertains to the many ways in which many actors, individuals and institutions, public and private, deal with risks. It includes formal institutions and regimes and informal arrangements. The paper will first develop an adaptive and integrative framework of risk governance and applies this model to the risks of urban planning. After a short summary of the roots of risk governance, key concepts, such as simple, uncertain, complex and ambiguous risks, will be discussed. The main emphasis will be on each of the five phases of risk governance: pre-assessment, interdisciplinary assessment, risk evaluation, risk management and risk communication. The paper will explain how these phases of risk governance can be applied to the area of urban planning and improve the dynamic sustainability of cities.