Grid systems are currently being used and adopted by a growing number of user groups and diverse application domains. However, there still exist many scientific communities whose applications require much more computing resources than existing Grids like EGEE can provide. The main objective of this project is to support these new communities:a) by providing the necessary extensions for existing Grid infrastructures to address the specific needs in these new scientific communities within a coherent pan-European model, regardless of the location of their research facilitiesb) with the adaptation of their applications to the enhanced Grid infrastructurec) through the provision of standard APIs and Grid application development tools that facilitate the adaptation of their application to the enhanced Grid infrastructure.In order to support the specific needs of these scientific communities EDGeS will interconnect the existing EGEE Grid infrastructure with existing Desktop Grid (DG) systems in a strong partnership with EGEE. Service Grids (SGs) like EGEE are more flexible than DGs and can accommodate a broader variety of applications, however, they are much more expensive to maintain. Desktop Grids are currently restricted solely to Master/Worker-style compute-intensive applications but can scale very easily and are able to collect 1-2 orders of magnitude more compute power than most SGs are able to, and at a fraction of the cost. The interconnection of these two types of Grid systems will enable more advanced applications and provide extended compute capabilities to more researchers.One other objective of EDGeS is to extend the potential user communities for both Grids and Desktop Grids beyond traditional scientists and current volunteer computing participants to further involve ordinary citizens, secondary school students, and company employees, giving them an opportunity to become involved in science and to apply Grid technology in their every day life.