The legislative authority is centred on Parliament, which is made up of two Houses, the National Assembly, which has 400 members, and the National Council of Provinces (NCOP), with 90 members. In order for a bill to become law, both Houses must approve it. A bill can be introduced by a Minister, a Deputy Minister, a parliamentary committee or an individual MP. However, most bills are drawn up by a government department under the direction of the relevant Minister or Deputy Minister. The majority of bills are introduced in the National Assembly, but certain bills that affect provinces may be introduced in the NCOP. The law-making process usually starts with the introduction of a Green Paper – a discussion document drafted by the relevant department that is then subject to public consultation. The Green Paper may be followed by a White Paper, a more developed discussion document that broadly outlines government policy and may also be subject to review by interested parties. Once introduced, a bill is referred to the relevant committee, where it is debated in detail and, if necessary, amended. Then the House takes a decision on whether to pass the bill. The last general elections were held in May 2014 with the next due in 2019.