The move comes on the heels of the appointment of Andrew Robertson, 40, CEO of AMV BBDO in London, to the new position of president and CEO of BBDO North America.
Mr. Sann also assumes the post of chairman of BBDO New York.
In addition, Bill Katz, 46, becomes the sole CEO of the New York office, a position he once shared with Mr. Sann.
The job title shift is more than just a cosmetic change for Mr. Sann. It cements his position as the heir apparent to BBDO's legendary creative guru, Phil Dusenberry, 63, chairman of BBDO North America.
Mr. Sann, in his capacity as creative chief of the agency's New York flagship office, traveled the country, helping to oversee the creative output of the agency's U.S. shops.
In his new position, "he won't be going to them. They'll be coming to him," quipped Mr. Katz.