This lecture develops a theorization of "speculative policing": an experimental, future-oriented form of policing that connects crime prevention to real estate speculation and other forms of negotiating urban risk and uncertainty. Speculative policing works to establish a specific sociopolitical order; renders economically productive the differentiated and dynamic value of urban spaces and populations; and involves flexible, provisional interventions that anticipate failure and skirt the edges of the law. Speculative policing combines three future-oriented phenomena that engage with risk and uncertainty in different ways: preventive policing, real-estate speculation, and experimental modes of governance. These phenomena are in themselves not necessarily new; the specificity of speculative policing lies in the conjunction of these three phenomena in contemporary cities. Their combination implies the emergence of a new mode of urban security governance, a form of political and economic rationality that is speculative both in its underlying logic and in its everyday implementation.