A ministry is a specialized organization responsible for a sector of government public administration, sometimes led by a minister or a senior public servant, that can have responsibility for one or more departments, agencies, bureaus, commissions or other smaller executive, advisory, managerial or administrative organisations. Ministries are usually subordinate to the cabinet, and prime minister, president or chancellor. A government will usually have numerous ministries, each with a specialised field of providing public service. National ministries vary greatly between countries, but some common ones include Ministry of Defence, Ministry of Foreign Affairs, Ministry of Finance, and Ministry of Health. In the 20th century, Western countries (including monarchies such as Belgium and the United Kingdom) have trended away from the usage of the designation “ministry”, preferring to replace such with words such as department, agency, bureau or secretariat.