Enrique Leff (Mexico) is a Mexican economist, who defines himself today as an environmental sociologist and environmentalist. He has written 25 books and 180 articles on political ecology, environmental sociology, environmental economics, environmental epistemology and environmental education. He is regarded as one of the key environmental thinkers in Latin America. After a degree in chemical engineering from UNAM (Universidad Nacional Autónoma de México) in 1968 Leff graduated with a Doctorat de Troisième Cycle in development economics from the École Pratique des Hautes Études, Paris, in 1975. Leff lectured at UNAM (Universidad Nacional Autónoma de México) full-time from 1973-1986 before becoming coordinator of the Environmental Training Network for Latin America and the Caribbean (1986-2008) and coordinator of the Mexico City office of the Regional Office of Latin America and the Caribbean of the United Nations Environment Programme (2007-2008). In 2008, he returned full-time as professor of political ecology and environmental politics at UNAM. He is also senior researcher at the Institute of Social Research (Instituto de Investigaciones Sociales) at the same university. Leff works in Spanish, Portuguese, English and French.