Jonathan Powell (Labour adviser)
 Jonathan Nicholas Powell (born 14 August 1956) is a British diplomat who served as the first Downing Street Chief of Staff under British Prime Minister Tony Blair from 1995 to 2007. He was the only senior adviser to last the whole period of Blair’s leadership. During this period Powell was also the chief British negotiator on Northern Ireland. From 2007 Powell joined Morgan Stanley as a full-time senior managing director of its investment banking division.