Actor Ben Affleck attends BAFTA Los Angeles' 17th annual awards season tea party at The Four Seasons Hotel on January 15, 2011 in Beverly Hills, California. Credit: Jason LaVeris/FilmMagic

Whatever cause you hold near and dear, Ben Affleck wants you to do something about it.

The Argo star, 39, will honor a dedicated youth activist Sunday evening with a $100,000 prize at the Do Something Awards in Santa Monica, Calif. (The show will air August 21 at 9 pm on VH1.)

Affleck himself is a celeb Do Something nominee, along with Kristen Bell, Justin Bieber, Taylor Swift, Miley Cyrus, Nicole Richie, Neil Patrick Harris, Channing Tatum, Emma Stone and more.

The issue most important to the father of three? Fostering development opportunities for residents of the war-torn Eastern Congo; in 2009, Affleck founded the Eastern Congo Initiative to help do just that.