Parliamentary Private Secretary to the Prime Minister Bonar Law's Parliamentary Private Secretary, J.C.C. Davidson acted in effect as his Chief of Staff. Margaret Thatcher's downfall from the Conservative Party leadership in 1990 is attributed by many to the actions of her Parliamentary Private Secretary, Peter Morrison, in failing accurately to count votes amongst Conservative backbenchers. Some Parliamentary Private Secretaries to the Prime Minister go on to hold higher office; Lord Dunglass served as Parliamentary Private Secretary under Neville Chamberlain and later went on to serve as Prime Minister in his own right. There can be multiple Parliamentary Private Secretaries to the Prime Minister at a given time.
Prime minister Bahrain's prime minister, Sheikh Khalifah bin Sulman Al Khalifah has been in the post since 1970, making him the longest serving non-elected prime minister. The post of prime minister may be encountered both in constitutional monarchies (such as Belgium, Denmark, Japan, Luxembourg, the Netherlands, Norway, Malaysia, Morocco, Spain, Sweden, Thailand, Canada, Australia, New Zealand, and the United Kingdom), and in parliamentary republics in which the head of state is an elected official (such as Finland, the Czech Republic, France, Greece, Hungary, India, Indonesia (1945-1959), Ireland, Pakistan, Portugal, Montenegro, Croatia, Bulgaria, Romania, Serbia and Turkey (1923-2018)). See also "First Minister", "Premier",