Until a new government is formed, the previous National Government continues in a caretaker role.
It can deal with administrative and minor issues but is restricted from making significant decisions or appointments. By convention these are left to the incoming Government.
It is important this time because election night did not deliver a clear-cut result for the first time since 2005.
National's Steven Joyce said he had no intention of bucking the convention. The caretaker period meant keeping up with the normal "machinery of government", he said.
The Cabinet Manual says caretaker governments can implement decisions already made, but cannot decide on controversial issues, issues with long-term impact such as major contracts or significant appointments, or changes to policy.