Team members: Andrena Papantoniou, Carolina Libardi, Erina Filipovska In order to achieve environmental improvements and propose changes on the pollution issue of Barcelona, it was very important to understand the main generators of CO2 emissions and the roll of the urban vegetation. For this reason, we focused on the calculation of the overall CO2 emissions of transportation and buildings, and the CO2 consumption from vegetation. The outcomes of this research exposed the current giant pollution problem of Barcelona; the overall amount of CO2 emission are extreme (99.7%), whilst the relevant absorption is poor (0.30%). Conclusions-Proposals: 1.Green areas are not enough to compensate CO2 emissions inside the urban area. Vegetation should be used as a strategy to improve insulation of buildings and to promote the psychological effect of a greener city. 2.Neighborhoods cannot be monofunctional. To avoid daily displacement of people going to work, neighborhoods should be, at the same time, a place of housing and work. 3.Design “Smart Buildings”. Buildings are responsible for a big part of the emissions CO2 inside urban areas. The emissions come from energy usage, such us electricity and natural gas. Buildings should be resource-efficient and well insulated.