There are at least three sorts of difficulties that hamper successful promotion of the rule of law. Each of these would be lessened by integration of materials which RoL promoters commonly avoid. First, the rule of law depends upon many factors beyond what most lawyers know, or know how to know. These include non-state norms, attitudes, beliefs, practices and institutions. Secondly, this is not a peculiarity of societies where the rule of law is weak and in need of promotion, but true of all societies, including those of rule of law promoters. Recognition of this requires reconceptualization of what is required for law to rule. And that, in turn, would benefit from integration of thought from domains and disciplines that RoL promoters have hitherto tended to consider other people's business. Such disciplinary ecumenism might make them more alive to the ends of what they are trying to promote; less aimlessly tied to particular institutional means.