The ECOSPACE Integrated Project has developed an advanced collaborative workspace platform for eProfessionals. The technologies, services and collaboration tools have been developed, integrated and validated in various living labs addressing different contexts of eProfessional working. This paper reports about the Living Lab for Professional Communities of Innovation and covers three different user environments where innovative tools, services and practices have been experimented in different experimental settings. The first setting addresses the support of new work and collaboration practices in professional education. The second setting focuses on collaboration among business and research partners in promoting regional innovation. The third setting is about collaborative innovation in virtual communities. In the three settings, different user communities have adopted and experimented different sets of collaboration services. The paper presents the living lab methodology designed to launch, operate and monitor the different innovation and validation settings. Based on a cross-comparison of results and a longitudinal analysis, conclusions are drawn regarding the effectiveness of innovation services and collaborative platform, strategies to involve users and building user communities, and the effectiveness of the living labs methodology.