Lawmaking bodies in one polity sometimes incorporate the law of another polity “dynamically,” so that when the law of the foreign jurisdiction changes, the law of the incorporating jurisdiction changes automatically. Dynamic incorporation can save lawmaking costs, lead to better legal rules and standards, and solve collective action problems. Thus, the phenomenon is widespread. Dynamic incorporation does, however, delegate lawmaking power. Further, as the formal and practical barriers to revocation of the act of dynamic incorporation become higher, that act comes closer to a cession of sovereignty, and for democratic polities, such cessions entail a democratic loss. Accordingly, dynamic incorporation of foreign law has proven controversial both within federal systems and at the international level. The problem is most acute when nation states agree to delegate law-making power to a supranational entity. In order to gain the reciprocal benefits of cooperation and coordination, the delegation must be functionally irrevocable or nearly so. Representation of the member nation states within the decision-making structures of the supranational entity can ameliorate, but cannot fully compensate for, the resulting democratic losses suffered by those nation states. More broadly, the benefits of dynamic incorporation must always be balanced against its costs, including the cost to self-governance.