In Canada, the principal secretary is a senior aide, often the most senior political aide, to a head of government. Formerly, the position of principal secretary was the most senior one in the Canadian Prime Minister's office (PMO). However, since 1987, it has been second to the chief of staff position.
The Leader of the Official Opposition and most Premiers also have a principal secretary.
The role of the principal secretary may vary, depending on how the prime minister or premier structures the workflow in their office. This has sometimes led to ambiguity in clearly defining the distinction between the roles of principal secretary and chief of staff to the general public.[1]
The organizational structure of the Prime Minister's office has traditionally been hierarchical. Depending on the personal approach of the Prime Minister, the duties of managing, administrating and co-ordinating the activities of the PMO may belong to the Principal Secretary, the Chief of Staff, or another key advisor.
The Government of Canada does not maintain an official, complete list of persons that have held leadership positions in the PMO. The following list includes persons that have held the position of Principal Secretary, Private Secretary, Principal Private Secretary, Personal Secretary, or Secretary.