A Prime Minister is the leader of the political party that wins a general election and is therefore in charge of the Government. He or she chooses the other MPs to help run the Government (called cabinet ministers) and together they make decisions about how to run a country.
A PM’s power and influence are limited by their ability to get the support of parliament. They must also be able to manage the strong personalities and ambitions of their ministers. Successful Prime Ministers, such as Sidney Holland and Keith Holyoake, have been able to do this well and stay in office for long periods. Others have not been so successful and been forced out, for example Jim Bolger (1990-97) and Robert Muldoon (in 1980).
The Prime Minister must be able to persuade foreign leaders to agree with his or her policies. He or she may also have to negotiate with international bodies, such as the UN or the EU. In some countries, such as the UK, the Prime Minister has a special role in military and security matters.
In a democracy, a Prime Minister must be able to keep in touch with the thinking of the electorate. Opinion polls, by-elections and pressure groups can put considerable demands on a PM. It is therefore not uncommon for the defining priorities of a Prime Minister to change from what he or she originally intended. For example, the issue of football hooliganism was a major focus for Margaret Thatcher’s premiership despite her original opposition to the use of cages at stadiums.