Emerald ash borer (EAB; Agrilus planipennis Fairmaire (Coloeptera: Buprestidae)) is an invasive beetle first detected in Michigan and Canada in 2002. We are doing genetic comparisons of EAB populations collected in the invasion zone (Great Lakes region) with EAB collected from its native range in Asia, to determine the sources population(s) that led to the North American populations, and to characterize EAB invasion genetics, focusing on whether there was a single or multiple introductions into North America and the possible age(s) of the infestation(s). To date we have obtained EAB population samples from Michigan, Indiana, Ohio, Ontario, Japan, South Korea, and China, but have been unable to obtain EAB samples from Mongolia, Taiwan and Russia. Here, we present a phylogenetic analysis of mitochondrial cytochrome oxidase I (COI) sequences, an analysis of AFLP fingerprints obtained using two selective primer pair combinations, and preliminary data on microsatellite variation in EAB populations. Based on the COI and AFLP data we have collected to date, North American EAB appear to be most closely related to EAB from China, although our data do not allow us to rule out South Korea as the geographic origin of North American EAB. Our ability to make strong inferences about EAB populations has been hampered by the scarcity of EAB specimens available from Asia. We also report the results of an extensive field trip to South Korea, China and Japan in the summer of 2006, and on the incorporation of the newly collected EAB individuals into our genetic analyses