American Humanist Association

The mission of the American Humanist Association is to advance humanism, an ethical and life-affirming philosophy free of belief in any gods and other supernatural forces. Advocating for equality for non-theists and a society guided by reason, empathy, and our growing knowledge of the world, the AHA promotes a worldview that encourages individuals to live informed and meaningful lives that aspire to the greater good.

http://americanhumanist.org/