A volatile organic analyzer (VOA), developed by Graseby Dynamics, Ltd. under contract to the Johnson Space Center Toxicology Laboratory, is the core instrument for trace contaminant monitoring on the International Space Station (ISS). The VOA will allow trace amounts of target compounds to be analyzed in real time so that ISS air quality can be assessed in nominal and contingency situations. Recent events on Mir have underscored the need for real-time analysis of air quality so that the crew can respond promptly during off-nominal conditions. The VOA, which is based on gas chromatography/ion mobility spectrometry, is the first spacecraft instrument to be used for such a complex task. Consequently, a risk mitigation experiment (VOA/RME) was flown to assess the performance and engineering aspects of the VOA. This paper is a review of VOA/RME results from the STS-81 and STS-89 flights and their implications for the ISS VOA design and operations.