LIFE SIRIUS overarching ambition is to improve governance in urban air quality planning and management, considering a holistic environmental approach through advancing knowledge, skills and competences of the responsible authorities, by providing: (b) a tangible pathway in order to scale-up and accelerate solutions aiming at tackling air quality issues, giving emphasis on health impacts and compound effects, and (c) a robust framework for increasing awareness of environmental issues associated with poor air quality. The project brings together 7 partners of excellence from 3 EU Member States (Greece, Cyprus, Italy) with a representative geographical coverage concerning the targeted environmental problem (air quality), cross-cutting complementary competences and excellent track records in European projects. LIFE SIRIUS will improve the quality of public authorities of the three targeted areas (Thessaloniki/Greece, Rome/Italy, Nicosia/Cyprus) at all levels in relation to preparatory, mitigation and adaptation actions foreseen in respective AQPs with two main goals: 1. Increase the capacity and improve the effectiveness and efficiency of public administration of the three regions involved in the project to upgrade the performance of AQPs in each city. 2. Develop common evaluation system regarding health effects of air pollution and future scenarios that will assess the evolution of the situation in selected future periods. LIFE SIRIUS will develop an Environmental Management System as a vital decision support tool that will enhance AQPs and accommodate multidimensional elements for efficient and operational information flow, facilitate management decisions for corrective actions and enhance cooperation between decision-making bodies in the scope of AQP implementation.