A year after its establishment, OPEC welcomed Qatar to its ranks. Subsequent years saw the additions of several African countries (including Algeria, Libya, Nigeria, Gabon, and Angola) as well as the United Arab Emirates, Ecuador, and Indonesia. Gabon and Indonesia have since left the organization. Ecuador suspended its membership in 1992 and did not rejoin for another 15 years.
In 1965, the group transferred its headquarters from Geneva, Switzerland, to its present-day base in Vienna, Austria.
In 1973, the Arab nations of OPEC imposed an oil embargo on the United States and some other Western countries because of their support of Israel in the Yom Kippur War that year. The embargo, which ended in 1974, led to a burgeoning energy crisis in the West.
Today, OPEC members have begun to focus on increasing their degree of collaboration to craft environmentally sound policies that also support developments within the oil industry.