In the United States, election night is followed by a monthslong transition period before the new administration takes office. In Britain, by contrast, new leaders endure a sleepless, 24-hour maelstrom that takes them straight from the campaign trail to No. 10 Downing St., the prime minister’s official residence and office.

With the election result increasingly clear, Prime Minister-elect Keir Starmer must travel to Buckingham Palace to be formally appointed by King Charles III, a ceremonial ritual in Britain’s constitutional democracy. It will be the king’s first post-election appointment, but he has some way to go before he equals the 15 prime ministers who served under his mother, the late Queen Elizabeth II.

The new prime minister then travels to Downing Street, which will have been swiftly vacated by his predecessor. There he will address the nation outside its famous black door, then be applauded inside by civil servants. Then come the security briefings — including on protocols in case of nuclear attack — calls to world leaders, and finally the small matter of running the country.