AbstractThis paper reviews the importance to identify the introduced fungal biological control agents as part of an environmental risk assessment, and the molecular and nonmolecular methods available for identifying the genetic variability in biological control fungi. A case study of the release of an exotic fungal pathogen (Entomophaga grylli) of insects, including Camnula pellucida, Melanoplus sanguinipes and M. differentialis, into the prairie ecosystem is presented.