Corporate governance is primarily the study of the power relations among a corporation's senior executives, its board of directors and those who elect them (shareholders in the "general meeting" and employees). It also concerns other stakeholders, such as creditors, consumers, the environment and the community at large. One of the main differences between different countries in the internal form of companies is between a two-tier and a one tier board. The United Kingdom, the United States, and most Commonwealth countries have single unified boards of directors. In Germany, companies have two tiers, so that shareholders (and employees) elect a "supervisory board", and then the supervisory board chooses the "management board". There is the option to use two tiers in France, and in the new European Companies (Societas Europaea).
Recent literature, especially from the United States, has begun to discuss corporate governance in the terms of management science. While post-war discourse centred on how to achieve effective "corporate democracy" for shareholders or other stakeholders, many scholars have shifted to discussing the law in terms of principal–agent problems. On this view, the basic issue of corporate law is that when a "principal" party delegates his property (usually the shareholder's capital, but also the employee's labour) into the control of an "agent" (i.e. the director of the company) there is the possibility that the agent will act in his own interests, be "opportunistic", rather than fulfill the wishes of the principal. Reducing the risks of this opportunism, or the "agency cost", is said to be central to the goal of corporate law.