The PI has developed a miniature time-of-flight mass spectrometer (TOF-MS), which can be op-timized for space and extraterrestrial applications, by using a revolutionary ion-focusing scheme. The instrument is optimized for a matrix assisted laser desorption/ionization ion source. The design is compact and the device that will be built under a Phase II grant will have a mass of less than 1 kg, a volume of less than one liter and draw approximately 3.5 Watts, exclusive of vac-uum generation, laser and sample-handling equipment. The proposed device will include a sam-ple-handling component, which will slightly increase the mass, volume and power requirements. Although there are several miniature TOF-MS systems currently available (NASA has a design available for licensing) the proposed innovation will out-perform all of the miniature designs currently available by 1 to 2 orders of magnitude (resolution and sensitivity) and has mass resolution comparable to current full-size research instruments. For commercial applications where volume, mass and power requirements are not so stringent, a device that performs better than current full-sized instruments can be designed.