In a previous article, I talked about how we need to build a smart identity for a smart city. The article, hopefully, pointed to building a perspective on what smart actually means. But, smart cities are built up from many smart pieces. These ‘smart pieces’ are really just an evolution of our current critical infrastructures (CI). The U.S. government, have named 16 essential sectors that come under the heading of ‘critical infrastructure, this includes transportation, energy, healthcare, and water. We are currently living through a movement from, once, disconnected and distinct, sets of CIs, to highly connected entities. Each area of CI, each sector in the smart city, will be directly, or indirectly linked. And, the glue that binds them is data. I believe that because of the criticality of data within the context of a smart city, perhaps data should be viewed as a critical infrastructure in its own right and even given ‘superstructure status’.