Does the name of the special interest group, "The Experimental Analysis of Human Behavior," imply that those who analyze the behavior of human animals must organize themselves apart from those who analyze the behavior of nonhuman animals? Is the use of nonhumans in experiments really not relevant to the analysis of the behavior of humans? If so, then something must have changed. Many differences exist, of course, between the behavior of humans and nonhumans-humans, for example, cannot fly under their own power-but have we really isolated differences in principle, differences that require separate organizations for the study of each? I will try to indicate why I believe this is a serious concern, where the concern comes from, and what, perhaps, might be done to maintain what was once a flourishing bidirectional relation between research with humans and nonhumans, in both basic and applied research.