Chapter 22 steps back from specific historical accounts to discuss more sweeping models that may explain the development of modern corporate law. Despite historians’ oft-expressed resistance to theoretical models, it argues that such models are useful in identifying both the most significant empirical facts to be discovered and which research questions should be asked. As the author writes, ‘history (in the sense of the empirical project of representing the past) and models need each other’. He then explains how evolutionary models—models that assume the law, in this case, is ‘significantly determined by competition between various actors over resources’—can go far to explain aspects of the development of corporate law, taking as his example the well-known development of modern US corporate law and specifically the triumph of Delaware law. Looking at three rival evolutionary models of regulatory competition—horizontal (state v state), vertical (state v Federal government), and intrastate (between interest groups)—he concludes that a model incorporating both state-versus-Federal competition and in-state interest group competition best explains the enduring dominance of Delaware corporation law.