This paper examines the cost and performance characteristics of six different field analytical instruments capable of accurately identifying and quantifying volatile organic compounds (VOCs) at the parts-perbillion level. Five-year life-cycle costs for the six field instruments including purchase, modification, and operational costs, were compared to the costs of using a stationary commercial analytical laboratory to obtain identical VOC data. The present-value life-cycle cost of a single soil or water VOC analysis was calculated for the six field alternatives and for the commercial laboratory at both a fixed annual sample analysis rate and at maximum capacity. The total cost of a single field analysis event was found to be approximately 18% of the total cost of sending that sample to a commercial laboratory. Cost differences between alternatives were correlated to variations in performance capabilities. 2269