State attorneys general are major participants in intergovernmental relations in the United States. This article presents six models that may explain their interactions with each other and tests three hypotheses associated with two models. Their interactions comport with the cooperative and the innovation-diffusion models. Only limited evidence supports the hostility model and its associated hypothesis. No evidence supports the mercantilist and competitive models. The response from only one attorney general suggested his actions are based on the benign neglect model. The conclusion is drawn that the cooperative activities of the attorneys general have produced a more harmonious federal system in terms of enforcement policies.