Sir William Alexander "Bill" Jeffrey, KCB (born 28 February 1948) is a former senior British civil servant, who retired in the autumn of 2010. Jeffrey was educated at Allan Glen's School, Glasgow, and the Glasgow University. He joined the Home Office in 1971. From 1998 until 2002 he was Political Director of the Northern Ireland Office, supporting the Prime Minister and successive Secretaries of State on the implementation of the Good Friday Agreement. He was subsequently Britain's most senior immigration official - director-general of the Immigration and Nationality Directorate - from 2002 to 2005.