NEW YORK: Hill & Knowlton said that global chairman and CEO Paul Taaffe has resigned from the WPP agency just days after fellow H&K veteran MaryLee Sachs announced plans to leave the firm.

Jack Martin, founding chairman of Austin, TX-based Public Strategies, has been named global chairman and CEO of H&K, effective immediately. Martin is now based in New York, where H&K has its headquarters.

H&K merged with sister WPP agency Public Strategies in November. At the time, Martin became global ...