Mr. Stewart commenced his career in Seismic Surveying in 1978 as a conventional surveyor in Alberta and has worked in the Surveying field full time since then, working on projects throughout Canada, United States, Jordan, Venezuela, Bolivia, Argentina and the Arctic.  Associated with GPS since before it's inception, with Doppler satellite receivers, Mr. Stewart has seen GPS evolve from only a handful of scientific users to the current global use of the GPS and GLONASS systems.