  Reflecting upon the sustainability challenges cities will be facing in the
near future and the recent technological developments allowing cities to become
"smart", we introduce IDEAL-CITIES; a framework aiming to provide an
architecture for cyber-physical systems to deliver a data-driven Circular
Economy model in a city context. In the IDEAL-CITIES ecosystem, the city's
finite resources as well as citizens will form the pool of intelligent assets
in order to contribute to high utilization through crowdsourcing and real-time
decision making and planning. We describe two use cases as a vehicle to
demonstrate how a smart city can serve the Circular Economy paradigm.
