In general, agroecology deals with different topics and questions related to agricultural production. In the last two decades, the term agroecology has been increasingly used with different meanings (Wezel et al., in press). On the one hand it is used for the scientific discipline of agroecology, that will be the topic of this paper; but, on the other hand the term agroecology is also used in the sense of a movement or as an agricultural practice (Wezel, 2007; Wezel, et al., in press). Environmental movements in the 1960s often emerged in opposition to industrialized agriculture, when public policies did not consider the environmental impact of agriculture, in particular pesticides, or the social aspects of rural development. Initially, the term agroecology was not used explicitly to describe a movement. It was only in the 1990s when the word started to be used in this sense, especially in the USA and in Latin America, to express a new way of considering agriculture and its relationship to society, and its place within it.