In this paper we argue that behavior analysts have tended to neglect the study of important aspects of complex human behavior, including cognition and emotion. This relative neglect has been costly in terms of mainstream psychology's perception of the field of behavior analysis and in terms of our ability to provide a more thorough account of human behavior. Observations and findings from the clinical context are offered as examples of behavior that are not readily explained by the three-term contingency, and we argue that an adequate account of these behaviors must include principles derived from recent behavior-analytic work, in particular a better understanding of the short- and long-term effects of establishing operations. The concept of the establishing operation and its implications for understanding complex human behavior are discussed.