A three day live trial to validate the SESAR dynamic Demand Capacity Balancing (DCB) concept started on 8 November 2011. The aim of this concept is to improve air traffic flow and capacity management (ATFCM) by 2013. It will reduce traffic complexity and streamline air traffic controller workload, thus improving capacity and safety. The trial is part of the first SESAR Release and involves Flight Management Positions (FMPs) from London, Reims and Maastricht, the Network Manager and eleven airlines.