The strategic goal of BESOS is to enhance existing neighborhoods with decision support system to provide coordinated management of public infrastructures in Smart Cities, and at the same time provide citizens with information to promote sustainability and energy efficiency.The project will target two main stakeholders: the owners of the infrastructure –municipalities – and its operators – ESCOs. The former will be provided with a Business Balance Score Card to audit the SLAs established with the ESCOs against a number of KPIs. The latter will make use of the same tool to analyze new business models, and will be also provided with a DSS Cockpit to Monitor and Control information from the infrastructure and establish coordinated energy efficiency strategies.Different Energy Management Systems within a smart city will be able to share data and services through a new Open Trustworthy Energy Service Platform. Stakeholders as ESCOS, public authorities, Distribution and Transmission System Operators, and domestic users, will be able to access and interface the existing infrastructure in smart cities.As an additional benefit, the deployment of such platform will open new opportunities to mobile application developers willing to increase energy efficiency awareness among citizens.BESOS will be tested in two leading cities: Lisbon and Barcelona. The assets that are available for the trials include: public lighting (>150000 luminaries), public buildings (>150), residential buildings (250), PV micro-generation (55 installations), wind turbines, smart heating, cogeneration, electrical vehicle charging points (> 250), and mobility systems (> 40000 traffic lights). In total >250GWh/year of consumed electricity and 168 MWh/year of produced electircity.The transferability of results is guaranteed by the strong involvement of BESOS consortium –e.g. ETRA, the municipality of Barcelona- in the City Protocol Society, where more than 30 worldwide capital cities participate.