The Tower Heist star is working with his Stiller Foundation to help Haitians recover for the massive 2010 earthquake that damaged much of the country's infrastructure.
Stiller toured Haiti last week and met with telecommunications company Digicel Foundation to develop ways to improve the island nation's education system.
He tweeted: "Great day in Haiti. Signed an agreement with Digicel Foundation to build 8 schools..."
Stiller has previously organised a variety of fundraisers for Haiti, including a September auction that he co-hosted with former US President Bill Clinton.
The actor will next appear alongside Vince Vaughn and Jonah Hill in the sci-fi comedy Neighborhood Watch, which opens on July 27, 2012 in the US and August 22 in the UK.
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Watch Ben Stiller launch his 'See Jennifer Aniston Naked Foundation' for poverty relief below: