Data and technology have become the accelerant to achieving smart city goals. Infrastructure in the 21st century will contain a confluence of devices that include power-efficient sensors, wireless networks and mobile-centric apps. Combined with an expansion of clean energy and smart-grid practices, these enablers are setting the connected, smart city table. Atlanta, Phoenix and Washington, D.C., are all actively involved in developing smart city infrastructure. Each city wants to transform in ways that sometimes look similar and sometimes different. Some smart cities are further along than others, but all are learning what works best for them as they employ data-collecting sensors, interactive devices and big data.