Ian R. Hall has traveled widely and his knowledge of mushroom cultivation is international in scope. His firm, Truffles & Mushrooms Consulting Ltd., aims to further the cultivation of edible ectomycorrhizal mushrooms. He also directs the activities of Symbiotic Systems N.Z. Ltd, a company that studies the beneficial effects of mycorrhizas in forestry. Hall has published on a variety of topics in addition to edible mushrooms and mycorrhizas, including the pathology of grasses oversown into tussock grasslands and greenhouse design. He completed his PhD at New Zealand's Otago University, where he studied with Geoff Baylis. After his post-doctoral fellowship with Jim Gerdemann at Illinois University, Hall returned to New Zealand to work as an applied mycologist and plant pathologist with the Ministry of Agriculture and Fisheries (MAF Technology).Steven L. Stephenson, a professor at the University of Arkansas, has collected and studied fungi for more than thirty-five years, and his research program has taken him to all seven continents and every major type of terrestrial ecosystem.