The environmental awareness began on the 70’s with the United Nations Conference on the Human Environment claiming that adequate measures should be implemented to face these problems (United Nations, 1972). Still, only in the 80’s sustainability has emerged as a clearer concept, when the World Commission on Environment and Development brought it into mainstream and defined sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their needs” (Harlem, 1987, p.41).