Central-Eastern European countries have exceptional geothermal resources. These resources are either unexploited due to the lack of technological know-how or their utilisation is carried out in an unsustainable way; geothermal district heating projects lack the energy efficiency component and the used thermal water is not reinjected but instead released to surface waters. Geothermal Communities will demonstrate best available technologies in the use of geothermal energy combined with innovative energy-efficiency measures in three different pilot sites (Hungary, Slovakia and Italy). Furthermore the project will integrate a large number of cities as project partners (from Serbia, Romania, Poland and Italy) that either already have ongoing geothermal systems that needs the adoption of new technologies (e.g. Sacueni, Romania) or they would like to implement new systems from scratch with the help of the project partners (e.g. Subotica, Serbia). In addition to the demonstration component through the parallel implementation of three ambitious development works there is also a strong complementary component of research focusing on making geothermal projects more cost efficient and technologically sound. Results of the project activities will be disseminated via straightforward dissemination actions combined with a training programme organised for municipal-level decision makers. Finally, the Mayors’ Geothermal Club will be set up and will continue operating even after the EC-funded period as a permanent network of city mayors and municipal-level decision makers who are interested in the sustainable utilisation of geothermal energy.