The gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), has methodically invaded the United States since its introduction outside of Boston, Massachusetts in 1869, and is currently established from eastern Wisconsin to northern North Carolina. As the gypsy moth colonizes new areas, entomopathogens that infect larvae, such as the fungus Entomophaga maimaiga and gypsy moth nucleopolyhedrovirus (LdMNPV), eventually disperse into new gypsy moth populations, but it is not known how long it takes for these pathogens to naturally follow. We conducted empirical studies in central and southern Wisconsin in 2005-2007 to quantify the movement of entomopathogens and to understand the association among pathogen incidence, gypsy moth abundance, and the time since initial gypsy moth establishment. These field data were then used to derive a space-time model of E. maimaiga and LdMNPV spread to better understand their role in gypsy moth invasion dynamics specifically at the gypsy moth population front.