Robert Ewing has over 20 years of experience as an analytical chemist with extensive expertise in trace detection analysis of explosives, drugs, and chemical weapon materials. Robert has held positions at Edgewood Chemical and Biological Command, Idaho National Laboratory, and New Mexico Institute of Mining and Technology. In 2006, Robert joined PNNL and is currently a senior research chemist, a project manager, and technical team leader for the Chemistry and Materials team. As an analytical chemist, he specializes in ion-molecule chemistry at atmospheric pressure as related to ion mobility spectrometry and mass spectrometry. His fundamental studies have resulted in advances to the sensitivity, selectivity, and expanded applications of ion mobility spectrometry and mass spectrometry technologies. Recently, Ewing developed a breakthrough technology that demonstrated, for the first time, real-time vapor detection of explosive compounds such as RDX and PETN at parts-per-quadrillion levels. Results from his research have resulted in 39 peer-reviewed publications, numerous national and international presentations, and four patents. Ewing’s experience spans fundamental research to application development to testing and evaluation. His expertise has expanded outside of the lab to include field deployment of instrumentation including training and working with private companies in the development of commercial instrumentation. As a chemistry professor he taught graduate- and undergraduate-level courses and mentored students in research activities. Ewing is currently serving as the past-president of the International Society for Ion Mobility Spectrometry.