One increasingly visible expression of alternative masculinities around the globe is men's involvement in efforts t prevent men's violence against women. Men who take part in such efforts, for example, as activists or educators, take up projects of personal change as well as vider social change. They seek to be "the change they wish to see in the world," working to undermine their own gender privilege and to act in gender-equitable and nonviolent ways. This chapter focuses on such men. It examines men's paths to involvement in collective projects to prevent men's violence and to build gender equality, the personal transformations men undergo, and the ways in which they may be complicit with patriarchal gender relations, conclulding with an examination of the complexities of addressing personal and institutional privilege.