An ex officio member is a member of a body (a board, committee, council, etc.) who is part of it by virtue of holding another office. The term is Latin, meaning literally "from the office", and the sense intended is "by right of office"; its use dates back to the Roman Republic.
According to Robert's Rules of Order, the term denotes only how one becomes a member of a body. Participatory rights of ex officio members may or may not be limited by the body's regulations or bylaws. In some groups ex officio members may frequently abstain from voting. Unless regulations or bylaws constrain their rights, however, they are afforded the same rights as other members of the body, e.g., proposing motions, and voting.
Any ex officio membership (for example, of committees, or of the board) will be as defined by the nonprofit association's bylaws or other documents of authority. For example, the bylaws quite often provide that the organization's president will be ex officio a member of all committees, except the nominating committee.
According to the Constitution of the Communist Party of China, the General Secretary of the Central Committee must be a member of Politburo Standing Committee.
As of 2007[update], the Executive Council of Hong Kong is still composed of ex officio members (official members since 1997) and unofficial members (non-official members since 1997). By practice the ex officio members include the secretaries of departments, i.e. the Chief Secretary, the Financial Secretary and the Secretary for Justice. Since 2002 all secretaries of bureaux are also appointed by the Chief Executive to be official members of the Executive Council. But since 2005 the secretaries of bureaux attend only when items on the agenda concern their portfolios.