Bipolar objects are common in archaeological assemblages. Produced by hammer-and-anvil knapping, these objects generally are classified in one of two conflicting ways: as cores or as wedges. Although most archaeologists take the first view, the second remains prevalent in some quarters, especially in eastern North American Paleo-Indian studies. Setting forth and evaluating the corollaries of both views, this article concludes that most bipolar objects—even in Paleo-Indian assemblages—are cores. It also documents ethnographic observations of bipolar reduction at some length.