The Oscar winner turned up in Washington, D.C., today with the Secretary of State to raise awareness for an initiative aimed at preventing children in the Democratic Republic of Congo and around the globe from dying of preventable diseases.
The conference, titled Child Survival: Call to Action, was organized by the non-profit Eastern Congo Initiative, which Affleck founded in 2009 to draw attention to economic and social development in the Congo and help create a sustainable future for the country.
"We wouldn't allow four year-olds to die from preventable diseases in the U.S.—nor should we let it happen in Congo or anywhere else," Affleck tweeted on Tuesday.
The conference hopes to rally support for efforts to reduce the Congo's infant mortality rate.
Affleck next returns to the big screen in the Iran hostage drama Argo, hitting theaters in October.