On June 15, Donald T. Grimes will be joining Neiman Marcus Group as executive vice president, chief operating officer and chief financial officer. Karen Katz, president and CEO of Neiman Marcus Group, made the official announcement Monday. Grimes will succeed Jim Skinner, who will fill the newly created vice chairman position. “Don is an excellent choice to serve as our new chief operating officer and chief financial officer,” Katz said in a news release.