Accenture Plc. said late Thursday its board of directors has named Julie Sweet the company's new chief executive officer, and that David Rowland, interim chief executive officer, has been appointed executive chairman. Marge Magner, Accenture's non-executive chair of the board, will resume her role as lead independent director, Accenture said. The changes are effective Sept. 1. Sweet currently serves as chief executive officer of the consultancy's North America business, the company's largest geographic market with revenues of about $18 billion. Sweet also served as Accenture's general counsel, secretary and chief compliance officer. Shares of Accenture were flat in the extended session after ending the regular trading day up 1.5%.