From 1986 to 1993, the United Shareholders Association (USA) provided a conduit through which small shareholders could unite and attempt to influence the governance of large US corporations. We show that the USA targeted large firms that underperformed the market, that its influence increased from 1990 to 1993, and that USA-Sponsored proposals were more successful when the target firm was a poor performer with high institutional ownership. The announcement of 53 USA-negotiated agreements is associated with an average abnormal return of 0.9% or a total shareholder wealth gain of $1.3 billion, suggesting that USA-sponsored shareholder activism enhanced shareholder value.