Affiliated Computer Services, Inc. (ACS) has renewed their lease at the River Ridge Office Building. River Ridge is located at 9040 Roswell Road in Atlanta's Central Perimeter submarket. REIT Management and Research recently acquired the 177,845-square-foot building. The new lease for 134,500 square feet, running through the year 2011, accounts for almost all of the building's eight stories. Dallas, TX-based ACS is a business process and IT outsourcing firm with more than $4 billion in annual revenues.