These days, IOs seem to have few friends and many critics. Their detractors alternately portray them as witless tools of the United States and other powerful states (Mutume 2005; Oatley and Yackee 2000) or as rogue actors who, in escaping the control of the states that created and comprise them, threaten national sovereignty (Miller 2005). Like most of the chapters in this volume, we reject such oversimplifications. The institutional design of some IOs allows them to engage in behavior undesired by their member states, while others are highly constrained and incapable of such independence. Nevertheless, even those agents capable of slack usually act as their principals intend. In 2003, the World Health Organization (WHO) took the unprecedented step of directly warning travelers away from countries with significant outbreaks of Sudden Acute Respiratory Syndrome (SARS). Both before and after this radical step, however, and for much of its history, the WHO staff eschewed actions that violate its contract with its members. In recent years, similarly, the World Trade Organization's (WTO) Appellate Body (AB) granted non-state actors standing in the WTO dispute settlement process, despite clear evidence that the member states saw the IO as overstepping its authority. Like the WHO actions, however, WTO behavior proved the exception to the rule; the WTO most often carries out its delegated functions in much the way its members intend.