The **Prime Minister** is the head of government in parliamentary systems, primarily responsible for setting government policy, overseeing the operation of government agencies and the Civil Service, and appointing members of the Cabinet and ministers. The Prime Minister leads the executive branch and is the principal government figure in the legislature, often the House of Commons or equivalent, depending on the country[1][2][5]. The role originated in 17th-century France but was formalized in Britain during the 18th century, evolving into a central figure in British and Commonwealth governance. The British model, exemplifying a "strong prime minister" system, has influenced many countries including Canada, Australia, India, and New Zealand[4][5]. The Prime Minister’s power includes controlling the legislative agenda, managing the civil service, determining government structure, and crisis management during national emergencies[1][4]. Key responsibilities include maintaining a parliamentary majority to pass legislation and budgets, chairing Cabinet meetings, setting agendas for Cabinet committees, managing relationships with opposition parties and devolved governments, and representing the government in Parliament and to the monarch or head of state[1][2]. The Prime Minister may also call elections and has significant influence over national policy and economic priorities[4]. Historically, the office has grown from informal leadership to a constitutionally recognized position with broad executive powers, though the extent varies by country. For example, in semi-presidential systems like Lebanon, the Prime Minister shares executive power with a President but must maintain parliamentary support[3]. In Australia, the Prime Minister is chosen by the governing party and must maintain majority support in the House of Representatives[6]. Currently, the UK Prime Minister is The Rt Hon Sir Keir Starmer KCB KC MP, who leads the government with the support of the Cabinet and ministers[2]. The Prime Minister’s role remains pivotal in shaping government direction, policy implementation, and political leadership, making it a critical focus for those interested in business and technology policy impacts globally.