Forests are a component of the natural capital which has provided, ever since forgotten times, the humankind with various services, acting as a shelter, fuel provider, construction material provider, food provider. Practically, the development of humankind cannot be either imagined than strongly connected to the forest. Less than acknowledged are though the ecologic services provided by the forest ecosystems, which take various shapes. One of the causes is the “subtlety” of these services, as they are harder to identify. Paradoxical, at first sight, the value of these services is mostly emphasized when they disappear, their lack being the consequence of human intervention on these complex ecosystems. Dysfunctions regarding their functioning, not to say about their total destruction lead to long term economic consequences, most of the times being devastating or hard to correct. Their usage value (the economic value) is easy to identify, as it can be immediately transformed into money through irrational exploitation of forest ecosystems, the temptation of the immediate advantage being high. But, on long term, the ecologic value, the “future option” value, despite the fact that they can be separately considered, they have a strong connection to the long ter economic values, as not to speak about the intrinsic, moral nature value. Practically, they validate the economic value, they amplify it, as it is the reason for which a knowledge on and a quantification of these service is needed, especially of the ecologic ones. In Romania, human pressure on forest ecosystems threatens the medium and long term economic development of the country, through irrational exploitation or through the decreasing of the forest fund, actions that are mostly abusive and illegal.