There are also countries that have both an elected president as the head of state and a prime minister as the head of government. In this case, these two positions share the responsibilities of political leadership between them. These systems are called “semi-presidential systems”.

Some countries have tried to combine the strong and stable system of government that is often associated with the presidential system with the more democratic and accountable system of the parliamentary system. The best known example of this comes from France, which has been copied in its original form, as in Sri Lanka and many African Francophone states.

Whether a mixed system operates more like a presidential or parliamentary system depends on the relative political strength of the president or prime minister. In most cases, the powers of the president are regarded as appropriate for times of acute national crisis, while the normal working of government depends on continued support from the legislature and is carried out by the prime minister. Nevertheless, presidents may try to expand their powers and may succeed when their party has a majority in the legislature. Thus, the mixed system does not preclude tensions between the president and the prime minister and can lead to politics of conflict and disunity in government, as is illustrated by the experience of the mixed system in Sri Lanka.