Proxy advisor for shareholder voting are a relatively recent phenomenon, globally and domestically. However, in recent days, ISS and other proxy advisors continue to draw significant attention from the corporations and financial regulators. Employed by an many institutional investors, proxy advisory firms provide analysis and voting recommendations on shareholder voting issues. More and more institutional investors have gradually outsourced their votes to those proxy advisors. However, the proxy advisors, by publishing their own governance principles and selling their voting recommendations, have become soft-law makers. This increasing influence of the proxy advisory activities has led corporations and financial regulators to question their legitimacy and the lack of oversight of those activities. One of the primary concerns raised by advocates of proxy advisor reform is the potential for conflict of interest that arises when a proxy advisor advises a company hot to structure management proposals to improve their chances of shareholder approval, while at the same time advising institutional investors how to vote their proxies for that proposal. Second concern is that proxy advisor firms wield significant influences over institutional investors. This is because institutional investors perceived that engaging a proxy advisor is the best way to comply with heir fiduciary duties to vote proxies for the benefit of their investors and to comply with disclosure obligations imposed by regulators. The precise extent to which proxy advisors influence shareholder votes remains open to debate, especially in local area. However, little doubt exists that proxy advisors have had a meaningful impact on some shareholder meeting issues, particularly those in connection with closely proxy contest. In light of this perceived influence, Part II of this Paper briefly provides an overview of the reason of rise of the proxy advisory industry, centered on the ISS and Lewis & Co. which dominates the proxy advisor market. Part III presents the current business model of both ISS and Lewis & Co. Part IV reviews the influence of proxy advisors on shareholders' voting rights and corporate governance. This section will also cover the various regulations and proposals emitted by foreign financial regulators to offer a better oversight of the proxy advisory industry. In light of previous research, Part V proposes a voluntary regulatory approach to the proxy advisors and to engage in self-regulation in considering the scarcity of competition in Korea.