A constitution is a plan of the structure and powers of government. Constitutions outline the rights, responsibilities and powers of each of the main institutions of government. They also set out the process of how governments make, implement, and enforce laws.

Constitutions set out the most basic rules about how government and politics work in a country. They contain permanent laws that determine how governments make (less permanent) laws and policies. Examples of these more permanent laws include citizens’ rights and rules about how the constitution can be changed. These basic laws need to be considered when governments make laws and policies that are necessary to run the country.

Most countries’ constitutions are written documents, however there are some (The UK, Israel and New Zealand for example) whose constitution is not one single document. Their constitutions are based on several documents and also unwritten understandings about how politics works in those countries.