The firm said that the moves come ‘in light of tremendous growth, impressive continued worldwide brand expansion and powerful operating metrics’.
Fontaine, 66, had been GameStop's chairman and CEO since the company's inception in 1996, and will now concentrate his focus on international operations, acquisition opportunities and strategic development.
DeMatteo, 60, who has been the COO since 1996 and Vice Chairman and COO since 2004.
J. Paul Raines, 44, former EVP of US Stores for home depot, will become the company's new COO, effective Sept. 7, 2008.
"Dan and I have worked together for over 12 years, and with an outstanding team of leaders, we have built GameStop into one of the fastest-growing and most successful specialty retailers worldwide," said Fontaine.
"Dan's move into the CEO role will assure the continuity of performance that has been a GameStop hallmark. His leadership, drive and insight into the videogame business and its huge upside potential make him the obvious choice as CEO."
"These moves are a natural evolution of our growth and potential, and I am excited about this opportunity," indicated DeMatteo.
"We are also extremely pleased to have Paul Raines join our executive team as COO. He brings a wealth of retail operations expertise and has an impressive track-record with executing strategies to support the customer experience and drive positive results. We're fortunate to have such a high caliber retail executive join GameStop."
Gamestop last week announced record Q2 results. The chain has 5,557 stores across 16 countries.