According to current estimates, more than three-quarters of the world’s oil reserves are located in OPEC countries. The bulk of OPEC oil reserves is located in the Middle East, with Saudi Arabia, Iran and Iraq contributing 56% to the OPEC total. OPEC countries have made significant contributions to their reserves in recent years by adopting best practices in the industry. As a result, OPEC proven reserves currently stand well above 900 billion barrels.