Macrolepidopteran caterpillars collected in 1995 and 1996 in the Monongahela National forest, Pocahontas County, WV, and the George Washington National forest, Augusta County, VA, yielded 60 previously unreported tachinid host associations. Most associations were between native species, but the introduced polyphagous tachinid Compsilura concinnata (Meigen) produced eight new associations with native hosts. The tachinids collected were slightly broader in their host preferences than associated Braconidae and Ichneumonidae, illustrating their potential importance in regulating foliage-feeding macrolepidopteran populations in the region studied. The sample years reported herein are the pretreatment baseline portion of a long-term study on the effects of Lymantria dispar (L.) defoliation, efficacy of applied Bacillus thuringiensis variety kurstaki Berliner, and the natural occurrence of the L. dispar pathogen Entomophaga maimaiga Humber, Shimazu & Soper on nontarget organisms.