Abstract Reawakened from its long slumber during the Cold War, the UN Security Council has become more active than ever before. Increased UN activity, however, has not always spelled increased accountability and control. This problem becomes particularly acute in the case of UN decisions imposing targeted economic sanctions on individuals who are suspected of sponsoring terrorism. These sanctions, or the process by which the decisions on sanctions are reached, have been in considerable tension with international as well as domestic conceptions of fundamental rights. When the UN enlists regional organizations and States in taking action against such individuals, the resulting multiplicity of institutions may be a blessing or a curse. The plurality of claims to ultimate legal authority may create multiple veto points checking for the protection of fundamental values or may provide myriad opportunities for obstruction, burden shifting, or evasion of responsibility. The difficulty, then, lies in arriving at an approach that can mediate productively between the needs for collective action and the particular perspective of each institutional participant without losing site of fundamental values, such as human rights. This Article tackles these questions by examining the international human rights constraints that operate on UN authority, and then turning to a discussion of the UN's economic sanctions regime and the clash of legal orders in recent litigation in the European Courts – especially in the Kadi case – surrounding implementation of that sanctions regime in the European Union and its Member States. We argue that the UN Security Council should be considered bound by human rights; that the EC Treaty provides the European Community with power to implement targeted sanctions; that the relation between the European legal order and that of the UN lacks an ordered hierarchy; and finally, that this pluralist relationship should be managed neither by usurpation nor simple resistance, but by constructive mutual engagement on constitutional as well as international human rights.