Corporate governance issues have become increasingly important to financial managers and shareholders. Firms that are plagued by poor performance, incompetent managers, or excess agency costs have become the subject of a dramatic increase in shareholder activism. Dissident shareholders, who are unable to launch costly takeover bids or proxy contests, have initiated a process of governance reform through the use of shareholder sponsored proposals. Shareholder proposals are a direct attempt to reverse operating or voting policies, such as a proposal to repeal a classified board. Managers announce shareholder proposals in a proxy statement and typically include a vote recommendation against the proposal. In the first essay, I find an unfavorable stock price reaction to the announcement of a shareholder proposal. In some cases, however, management supports the proposal and negotiates an agreement with the proposing shareholder. Stock prices react favorably to a settlement announcement. If managers are willing to negotiate with shareholders, they are perceived to be acting in the best interest of shareholders. If managers are unwilling, shareholders believe a severe agency problem exists. In the second essay, the effect that ownership structure has on voting outcomes of shareholder proposals is examined. I find a direct relationship between the percentage of votes cast in favor of the proposal and levels of institutional ownership. There is an inverse relationship between the percentage of votes and managerial ownership and firm size. Large firms with powerful owner-managers present the greatest obstacle to the success of shareholder proposals. The repeal of shareholder rights plans is one of the most frequently used shareholder proposals. By adopting the rights plan, managers increase the probability of defeating a takeover, but increase their power in negotiating with a potential acquiring firm. In the third essay, I find that firms who combine a rights plan with high debt levels construct a powerful defense against a hostile takeover. Shareholders target these high debt firms and design proposals to repeal the rights plan