Ecothess is the work of young scientists aiming to the strengthening of sustainability in Thessaloniki, Greece. Our main objectives are to raise public awareness and citizens’ participation towards social and environmental challenges. We believe that citizens should be aware of the information and relate versatile with their local community, seeking to increase the quality of life and environmental protection. In this context we are trying to create actions / tools that empower, inform and engage citizens to evolve together in smart citizens to shape a sustainable and smart Thessaloniki. Ecothess up to this date is structured in 3 main actions: the CityO^2 pavilion, the Ecothess Photo Contest, and the Ecothess Workshop.