UN Secretary-General Ban Ki-moon (L) and Ecuadoran President Rafael Correa attend the opening ceremony of the 3rd United Nations Conference on Housing and Sustainable Urban Development, or Habitat III, in Quito, capital of Ecuador, Oct. 17, 2016. The United Nations Conference on Housing and Sustainable Urban Development, held in Quito from Oct. 17 to 20, will set global standards of achievement in sustainable urban development for the next 20 years. (Xinhua/Santiago Armas)