The Commonwealth of Australia is a constitutional monarchy with a parliamentary system. It is based on the British Westminster model. The term Opposition has a specific meaning in the parliamentary system. Its formal title is Her Majesty's Loyal Opposition. This is an important part of the Westminster system. The Opposition directs its criticism at the Government and attempts to defeat and replace the Government. The Opposition is therefore the 'Government in waiting' and it is a formal part of the parliamentary system, just as is the Government. It is in opposition to the Government, but not to the Crown, hence the term 'Loyal Opposition'.