A Vice-Chancellor (commonly called the VC) of a university in England, Wales, Northern Ireland, New Zealand, Australia, India other Commonwealth countries, and some universities in Hong Kong, is the chief executive of the University. In Scotland and Canada the chief executive of a University is usually called Principal or President with Vice-Chancellor being an honorific.
Strictly speaking, the VC is only the deputy to the Chancellor of the university, but the Chancellor is usually a prominent public figure who acts as a ceremonial figurehead only (e.g., the Chancellor of Cambridge University is HRH The Duke of Edinburgh), while the Vice-Chancellor acts as the day-to-day chief executive. An assistant to a Vice-Chancellor is called a Pro-Vice-Chancellor or Deputy Vice-Chancellor — these are sometimes teaching academics who take on additional responsibilities. In some universities (e.g., Macquarie University, Deakin University), there are several Deputy Vice-Chancellors subordinate to the Vice-Chancellor, with Pro-Vice-Chancellor being a position at executive level ranking below Deputy Vice-Chancellor.
Canadian university Vice-Chancellors almost always carry the title of "President (or equivalent) and Vice-Chancellor": likewise, in Scotland, they hold the position of "Principal and Vice-Chancellor". In the Scottish practice the one individual may have two sets of official robes, reflecting a continuing division of responsibilities between the two posts.
In India most central and state level universities are administered by the Vice Chancellor, the highest paid official of the university. In deemed universities and institutes of national importance, the head of the institution is called the Director General or Director.
In the Republic of Ireland, day-to-day operations of the universities are under the directorship of a President (a Provost in the case of Trinity College Dublin). However, the president of each constituent college of The National University of Ireland also has the title of Pro-Vice-Chancellor of the NUI.
In the United States, a Vice-Chancellor is an assistant to a Chancellor, who is generally the (actual, not merely ceremonial) head of one campus of a large university which has several campuses. The head of the entire university is the University President (the equivalent of a Commonwealth Vice-Chancellor), the Chancellor is in charge of one campus, and a Vice-Chancellor is one of the chief assistants. Some systems, such as the California State University and Pennsylvania State System of Higher Education, invert this ranking so that the Chancellor is the head of the entire university.
At the University of the South, the Vice-Chancellor is the administrative head of the University (as well as the village of Sewanee). The Chancellor is the most senior Episcopalian Bishop of the owning Dioceses of the University. The Chancellor neither resides at the University nor holds administrative power; the Bishop holds ceremonial office only.
In the Philippines, in the University of Santo Tomas the day-to-day head of the University, as mandated by his duty as the Prior Provincial of the Philippine Dominican Province, the Dominican province that has majority control over the University.
As said earlier, The Vice Chancellor or the "Grand Vice Chancellor of the University of Santo Tomas" is only the deputy to the Chancellor of the university, but the Chancellor is usually a prominent public figure who is not always in the country (e.g., the Chancellor of University of Santo Tomas is the current Master of the Order of Preachers, the current being, Very Rev. Fr. Carlos Azpiroz Costa), OP, while the Vice-Chancellor acts as the day-to-day chief executive. The current Vice Chancellor of UST is the Prior Provincial of the Philippine Dominican Province, Very Rev. Fr. Quirico Pedregosa, OP.