 Most have a clear differentiation between the head of government and the head of state, with the head of government holding real power, much like constitutional monarchies (however in some countries the head of state, regardless of whether the country's system is a parliamentary republic or a constitutional monarchy, has 'reserve powers' given to use at their discretion in order to act as a non-partisan 'referee' of the political process and ensure the nation's constitution is upheld).Some have combined the roles of head of state and head of government, much like presidential systems, but with a dependency upon parliamentary power.For the first case mentioned above, the form of executive-branch arrangement is distinct from most other governments and semi-presidential republics that separate the head of state (usually designated as the "president") from the head of government (usually designated as "prime minister", "premier" or "chancellor") and subject the latter to the confidence of parliament and a lenient tenure in office while the head of state lacks dependency and investing either office with the majority of executive power.