Different driving forces push the electricity production towards decentralization. As a result, the current electricity infrastructure is expected to evolve into a network of networks, in which all system parts communicate with each other and influence each other. Multiagent systems and electronic markets form an appropriate technology needed for control and coordination tasks in the future electricity network. We present the PowerMatcher, a market-based control concept for supply and demand matching (SDM) in electricity networks. In a simulation study we show the ability of this approach to raise the simultaneousness of electricity production and consumption within (local) control clusters. This control concept can be applied in different business cases like reduction of imbalance costs in commercial portfolios or virtual power plant operation of distributed generators. Two PowerMatcher-based field test configurations are described, one currently in operation, one currently under construction