Since the late 1990s there have been many calls for reforms of the United Nations (UN). However, there is little clarity or consensus about what reform might mean in practice. Both those who want the UN to play a greater role in world affairs and those who want its role confined to humanitarian work or otherwise reduced use the term "UN reform" to refer to their ideas. The range of opinion extends from those who want to eliminate the UN entirely, to those who want to make it into a full-fledged world government. Secretary Generals have presented numerous ways to implement these new reforms. There have been reform efforts since the creation of the UN and closely associated with each of the Secretary-Generals.