Gender diversity in corporate America has become an increasingly popular topic for academic research. While extensively written about, no consensus has been reached to conclusively and consistently determine the relationship between the presence of women on a board and financial performance of the firm. This thesis contributes to existing literature by examining diversity through the lens of Rosabeth Moss Kanter’s Critical Mass Theory, questioning whether the third woman on a board truly serves as a “tipping point” for firm performance. Though the results are largely insignificant, we are able to establish that the Critical Mass Theory does not apply to ROA; the predicted impact of the first woman is greater than the impact of the third woman.