High densities of emerald ash borer (EAB) cause most large ash trees to die in about 5 years due, in part, to the lack of specialized parasitic insects that co-evolved with EAB in Asia as natural enemies. Forest Service scientists began studying the Asian parasitoids of EAB soon after its discovery in the United States and Canada in 2002. Five years later, the release of three parasitoid species from China was approved by federal and state of Michigan regulatory agencies, and their use as EAB biocontrol agents began. Successful establishment of these parasitoids in the United States led to the development of the EAB Biocontrol Program, including construction of a USDA Animal and Plant Health Inspection Service (APHIS) facility in Brighton, Mich., where the parasitoids are mass-reared. The rapid adoption of EAB biocontrol by states, tribes, and provinces is made possible by an online guide “Emerald Ash Borer Biocontrol Release and Recovery Guideline,” which was written by USDA scientists and is updated annually as new information becomes available. The guidelines provide detailed information for land managers to initiate EAB biocontrol programs locally, resulting in releases of EAB parasitoids throughout the ever expanding EAB infestation in North America.