Charles A.S. Hall received his Ph.D. in Systems Ecology under Howard Odum at UNC in 1970. He was professor at Cornell University, Univ. Montana and SUNY College of Environmental Science and Forestry. He is now very active as Professor Emeritus in Southern Oregon (see www.BPEInstitute.org). He is author or editor of 14 books and 320 scholarly articles and has been awarded the Hubbert-Simmons Prize for Energy Education and the Lifetime Achievement Award from the International Society of BioPhysical Economics. He is best known for his development of the concept of EROI, or energy return on investment, and a new field, BioPhysical Economics.