NASA, the Department of Defense, the Department of Homeland Security, and commercial industry have a pressing need for miniaturized, rugged, low mass, power efficient, high vacuum systems that can achieve vacuum pressures as low as 10E-8 torr while exhausting to greater than 1 atm. Advances in sensor technology at NASA and other government laboratories, in academia, and in industry, have led to the development of very small mass spectrometer detectors. However, the vacuum systems to support these sensors remain large, heavy, and power hungry. To meet this need, Creare proposes to build a compact vacuum pump based on the innovative combination of a turbomolecular pump to achieve hard vacuum pressures; a molecular drag pump to compress the gas through the transition regime of the gas; and a regenerative pump that compresses the gas further to exhaust to pressure greater than 1 atm. The pump represents an order-of-magnitude reduction in mass, volume, and power over current, commercially available, state-of-the-art vacuum systems that provide pumping over the same pressure range. Our unique vacuum pump design is based on technologies previously demonstrated at Creare that are combined in an innovative way to achieve the goal of providing vacuum pressures as low as 10E-8 torr while exhausting to greater than 1 atm in a small, low mass, power efficient package.