Principal Financial Group Inc. announced that Luca Maestri, executive vice president and chief financial officer of Xerox Corp., has joined Principal’s board of directors, effective today. “We are very pleased to welcome Luca to our board,” said Larry Zimpleman, Principal’s chairman, president and CEO, in a release. “His extensive international and financial experience will help guide our continued international expansion and leadership in global investment management and retirement services. Maestri joined Xerox as CFO in February 2011 after serving as CFO of Nokia Siemens Networks since 2008. Prior to that, Maestri held senior executive finance positions with General Motors Corp., where he worked for 20 years.