According to the Safe Cities Index published by the Economist Intelligence Unit, only four of the world’s smartest cities of Singapore, Tokyo, Amsterdam and New York City have made it into the top ten tier for personal, infrastructure and digital security. The primary aim of this paper is to determine how these cities have been able to adequately securitise where others have yet to match up. It applies a framework used by the US Department of Homeland Security’s Office of Cyber and Infrastructure Analysis to analyse how the adoption of smart technologies may actually increase the risk profile of a smart city, to which new gaps must be identified and closed.