Three taxa of big-eared bats (genus Corynorhinus) inhabit the Eastern United States. Rafinesque's bigeared bats (C. rafinesquii) are widely distributed from West Virginia to Texas whereas the Virginia big-eared bat (C. t. virginianus) and the Ozark big-eared bat (C. t. ingens) have limited ranges. Over the past 20 years, research on the biology, ecology, and conservation of bats throughout the world has increased, but research on big-eared bats of the Eastern United States has been less extensive. In evaluating the current state of knowledge, we reviewed the existing literature on big-eared bats that inhabit the Eastern United States and found 155 references, of which 101 were research notes, full articles, or review papers. In contrast, we found 239 references on the Indiana bat (Myotis sodalis), an endangered species with a similar geographic range size in the Eastern United States. Through our assessment of the literature on big-eared bats, we identified many gaps in our knowledge and understanding, including demography, population dynamics, social organization, hibernation and other aspects of physiological ecology, foraging behavior and diet, the effects of forest management, and the effects of conservation efforts. We also found that research on Virginia and Ozark big-eared bats has decreased in recent years while research on Rafinesque's big-eared bats has increased. Papers in these proceedings fill many of the knowledge gaps but much research is still needed to provide managers with the information they need to conserve these sensitive species.