One of the most fundamental divisions between forms of government is between presidential and parliamentary systems. This video describes how each of these systems works and highlights some of their implications for the representativeness and stability of democracy.

Presidential systems are governments where the president is the head of government as well as the head of state – in other words, where the president is the person in charge of running the country. In these systems, the president is typically elected directly by the general public (as opposed to by the legislature). There is also a separation of executive power, which is located in the president and the bureaucracy, from legislative power, which is located in the parliament. Presidents typically serve a fixed term in office (normally four or five years) and are chosen by elections that are held at regular intervals. Examples of presidential democracies include Brazil, Argentina, Chile – much of Latin America, in fact – as well as the United States of course.
In parliamentary systems, the head of government is the prime minister. The prime minister is elected a majority in the parliament, which can also remove him or her from power through a vote of no confidence. There is no separation between the executive and legislative branches of government — the bureaucracy reports to the parliament itself, through the prime minister. Examples include Canada, Japan, India, and much of the EU.
Parliamentary systems may have presidents, but in these countries the president only has a ceremonial role as the head of state. For example, Israel has a Prime Minister (currently Binyamin Netanyahu) and a President (Reuven Rivlin). Both are selected by parliament, but Netanyahu is the one who runs the country. President Rivlin signs laws and treaties approved by the Knesset, but doesn’t play a role in passing them. You can think of ceremonial heads of state as performing roles similar to the Queen in the UK.
Finally, there are mixed, or semi-presidential, systems. These countries have both a president and a prime minister, and they both have power within the government. Examples include France and Taiwan. In both of these countries, the president is directly elected and appoints the prime minister and the cabinet, but the parliament has the ability to remove the prime minister through a vote of no confidence.
Presidential and parliamentary systems each have their disadvantages. Presidential systems can be prone to gridlock and executive aggrandizement. They experience gridlock because there is a separation of executive and legislative power – if they are not held by the same political party, it may be difficult to pass legislation. They are prone to executive aggrandizement or democratic collapse because already concentrate a significant amount of power in the hands of one person.
Parliamentary systems, on the other hand, can be weak on accountability for two reasons. First, prime ministers are not directly elected by the public. They are typically the leader of the party with the most seats in parliament. This makes it easier to remove a prime minister, but when a leader resigns, the party chooses the new prime minister, not the public. For example, when Shinzo Abe resigned as Prime Minister of Japan in August 2020, his party selected his deputy Yoshihide Suga as the new party leader, who then became Prime Minister after a vote in the full Diet. Similarly, when Theresa May resigned as the British Prime Minister in July 2019, Boris Johnson became PM after a vote within the Conservative Party.
The second weakness (and strength) of parliamentary systems is that they are run by coalition governments. This is good for representativeness because a wide range of political views are included in government, but can be unstable and weaken accountability. Coalition governments can be short-lived if they are based on convenience as opposed to a more durable agreement. For example, Israel held elections in April 2019, September 2019, and March 2020 in an effort to get a configuration of parties that could form a stable government. In addition, having multiple parties responsible for passing legislation can make it difficult to identify one party to give credit or blame to if they choose to vote retrospectively (in other words, based on parties’ past performance) in elections.