As corporations grew through the 1970s and shareholding was divided among more widely dispersed shareholders in the U.S., CEOs, rather than shareholders, began to choose the board members. The CEO is able to run the daily operations of the firm and could recommend nominees to the board, after an increasing number of firms have failed to have a controlling shareholder. It is the managers who heavily influence the nominating process and cause the selection of board members in their own, and control over the nominating process machinery. The result of that change is that the board is effectively inferior to the CEO it is supposed to supervise. Modern corporate law of the U.S. has settled on a notion of a monitoring board. That means that the board has the ability to monitor management and maximize shareholder wealth. The monitoring function is described as the function which is at the heart of the agency cost model of the firm, because it identifies the central role for the board, necessary in light of managers' temptation to shirk or to act opportunistically. A monitoring board is composed mostly of independent directors, who don't have close personal or financial relations to the firm. But the independent directors are neither necessarily socially independent from management nor unsympathetic to the concerns of senior officers. The board's role become advisory at best rather than supervisory. One of the criticisms of the mandatory independent board of the U.S. is that it applies to all companies, regardless of the idiosyncratic needs or preference of a particular business type. There exists a need for improved corporate governance in the U.S. It is proposed an opinion that companies would be required to comply with the rules, or explain in their SEC filings why they have chosen not to do so. The dual board structure which would be composed of business review board and conflicts board is also proposed as an alternative of monitoring board by some scholars. The other opinion proposes an investor board, which would be a board of directors made up of representatives of various corporate constituents, including shareholders, creditors and senior managers. It is necessary to consider the improvement of independent board in Korea.