The Principal acts as the chief executive officer of the University under the authority of the Board and the Senate, and supervises and directs the academic and administrative work of the university and of its teaching and non-teaching staff. Since 1974, principals have been appointed for five-year terms, renewable subject to review. The formal authority for the appointment of the Principal rests under the Royal Charter with the Board of Trustees, although recent principals have been selected by a joint committee of trustees and senators. The office of the vice-chancellor has typically been held by the incumbent principal. In 1961, an amendment was secured by the Board to separate the office of principal from vice-chancellor if it wished. The first and only person to hold the office of vice-chancellor but not the office of principal was William Archibald Mackintosh. The current principal is Patrick Deane, serving as the twenty-first principal since 1 July 2019.