Catherine Livingstone will take over as chair of Commonwealth Bank when David Turner retires from the board at the end of December. Turner has been on the bank's board since 2006 and has served as chair since 2010.Livingstone joined the CBA board as a non-executive director earlier this year. She has been the chief executive of Cochlear and chair of Telstra.She is currently the president of the Business Council of Australia, a position she will give up next month.Commentary on Livingstone suggests that she will be a more hands-on chair than Turner, who is said to have given chief executive Ian Narev a free hand.Livingstone takes up another role in December, when she starts her term as chancellor of the University of Technology Sydney.