The US contains a massive resource of oil that has already been found, but which remains in known reservoirs after conventional production has reached its practical limits. This resource, over 340 billion barrels--2/3 of all oil ever discovered in the US--cannot be economically produced with currently available extraction technology and our current level of understanding of fluid flow in reservoirs. Improvements in both geological understanding and extraction systems will result from focused, interdisciplinary research and development. Although estimates vary widely, successful R and D could make producible as much as 80-100 billion barrels of this known oil--enough to sustain US production at current levels for the next 30--40 years. The realization of this potential has been the Federal oil program goal since its inception. This document, after summarizing the current situation, traces the program evolution and describes its present status. A knowledge of how the program has evolved provides a more informed perspective on the current effort. The document concludes with a brief discussion of the current strategy and its expected benefits. 45 refs.