My Oxford English Dictionary defines sustainable as “able to be maintained at a certain rate or level.” This means that one could use resources at the same rate or level seemingly indefinitely without drawing down on the ecosystem. Sustainable fishing would then mean catching only so many fish as to not disturb the overall population or other species dependent on the fish, such as birds and whales. Sustainable logging would be felling trees at a rate in which one could cut down trees at that rate forever without doing lasting damage to the forest.2