Keith F. Hartstein will become president and CEO of John Hancock Funds on July 18, said Elizabeth P. Kennedy, spokeswoman. He replaces James A. Shepherdson, the firm's president and CEO since May 2004, who resigned to join AXA Financial Services in New York. Mr. Hartstein was the firm's executive vice president of retail sales and marketing. Ms. Kennedy said no decisions have been made on replacing Mr. Hartstein. AXA Financial spokesman Jeff Tolvin confirmed that Mr. Shepherdson is coming to AXA Financial but would not provide further details.