Head of government

Head of government is a generic term used for either the highest or second highest official in the executive branch of a sovereign state, a federated state, or a self-governing colony, (commonly referred to as countries, nations or nation-states) who often presides over a cabinet, a group of ministers or secretaries who lead executive departments. The term "head of government" is often differentiated from the term "head of state", (e.g. as in article 7 of the Vienna Convention on the Law of Treaties, article 1 of the Convention on the Prevention and Punishment of Crimes against Internationally Protected Persons, including Diplomatic Agents and the United Nations protocol list), as they may be separate positions, individuals, and/or roles depending on the country.

The authority of a head of government, such as a president, or prime minister and the relationship between that position and other state institutions, such as the relation between the head of state and of the legislature, varies greatly among sovereign states, depending largely on the particular makeup of the government that has been chosen, won, or evolved over time.

In parliamentary systems, including constitutional monarchies, the head of government is the de facto political leader of the government, and is answerable to one chamber or the entire legislature. Although there is often a formal reporting relationship to a head of state, the latter usually acts as a figurehead who may take the role of chief executive on limited occasions, either when receiving constitutional advice from the head of government or under specific provisions in a constitution. For example, in the United Kingdom, the prime minister "advises" the Queen on the appointment of the cabinet, advice she is required to accept. On the other hand, the Queen's long service as the head of state enables her to provide the prime minister with information and insight into many matters to better run the government. However, because the United Kingdom is a constitutional monarchy, the prime minister uses her own discretion regarding whether or not to follow the Queen's advice. The Queen also is entitled to appoint a new Prime Minister.

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