Five9 (FIVN) announced that Five9’s Chief Financial Officer, Barry Zwarenstein has decided to retire, effective March 31. Bryan Lee, Five9’s Executive Vice President of Finance, has been appointed as interim Chief Financial Officer effective April 1, as the company conducts a formal search process for the CFO position. Zwarenstein will remain at Five9 to assist with the transition through June 30, and will continue as a consultant to the Company through September 30, the company stated.