There is a high degree of uncertainty about the impact that a rising GHG concentration can have on our planet temperature and thereby on life conditions. Continued research and the arrival of new information over time can contribute to reduce this uncertainty. Nevertheless, an early action against climate change is necessary to reduce the risks faced by us and future generations, thus mitigating the possibility of serious and hardly repairable changes. In other words we must invest to assure the future. On the other hand, actions against climate change must go hand-in-hand with improvements in energy efficiency and savings in the natural resources.