The Coalition advocates complete separation of church and state within American politics which they claim is clearly established in the U.S. Constitution under the First Amendment.

The mission of the Secular Coalition for America is to advocate for the equal rights of nonreligious Americans and defend the separation of religion and government.

The Society for Humanistic Judaism and the Freedom From Religion Foundation joined the Coalition in January 2006, the Military Association of Atheists and Freethinkers in February 2007, and the American Ethical Union in April 2008.

Coalition president Herb Silverman was a leading force behind the founding of the organization, which was designed as a framework for cooperation among secular groups in the United States.

Silverman believed that nontheistic Americans could gradually gain the respect of politicians and society if they collaborated on issues and presented a unified force for activism.

[14] Advisors to the Secular Coalition for America are Woody Kaplan (Chair), Rob Boston, Richard Dawkins, Daniel Dennett, Rebecca Goldstein, Sam Harris, Jeff Hawkins, Wendy Kaminer, Michael Newdow, Dan Okrent, Steven Pinker, Salman Rushdie, Todd Stiefel, and Julia Sweeney.

The Coalition is particularly active in challenging what it perceives as discrimination against nontheists by government chartered organizations like the Boy Scouts of America.

In 2007 the Secular Coalition for America pledged a $1,000 reward to the person identifying the highest level elected official to openly acknowledge no supernatural beliefs.