Despite women's impressive gains in education and the workplace over the past 50 years, men greatly outnumber women in leadership, especially in top positions. From corporate boardrooms to the halls of Congress, from universities to the courts, from religious institutions to philanthropic organizations, men are simply much more likely than women to be leaders. The report examines the environment in which leadership unfolds--in the classroom, in the workplace, and in politics. The academic and popular literature on women's leadership is vast and continuously growing. As a result, it is beyond the scope of this report to offer an exhaustive review. Instead, the authors identify key issues for creating lasting change, focusing on four questions: (1) What is the gender leadership gap? (2) What explains it? (3) What strategies have already helped narrow the leadership gap? and (4) And what can we do about it now? They conclude with recommendations on how to get to gender parity. [The report was edited by Rebecca Lanning. AAUW gratefully acknowledges the members of the Mooneen Lecce Giving Circle for their generous support of this report.]