This is the annual publication that presents the Bureau of Ocean Energy Management (BOEM) estimates of oil and gas reserves in the Gulf of Mexico Outer Continental Shelf. As of December 31, 2008, it is estimated that the Original Proved Reserves are 21.24 billion barrels of oil and 188.4 trillion cubic feet of gas from 1,270 proved fields. Original Proved Reserves are the total of the Cumulative Production plus Proved Reserves. This number includes 19 proved fields that were added during 2008. It also includes the 338 proved fields that have produced and expired. Estimates are derived for individual reservoirs from geologic interpretation and reserve evaluation. Cumulative Production from the proved fields accounts for 15.96 billion barrels of oil and 171.8 trillion cubic feet of gas. Proved Reserves are estimated to be 5.28 billion barrels of oil and 16.6 trillion cubic feet of gas. These reserves are recoverable from 932 proved active fields. For any field spanning State and Federal waters, reserves are estimated for the Federal portion only.