First day in office of Willy Claes, NATO Secretary General Brussels, Belgium 17 October 1994 Please credit NATO photos. Willy Claes, NATO Secretary General from 1994 to 1995. (NATO Photo 432Kb Ref. no: 14753/14) Ambassador Sergio Balanzino (Deputy Secretary General) greets Willy Claes (New Secretary General). (NATO Photo 704Kb Ref. no: 14744/11)