A direct aqueous injection (DAI) method was developed for the determination of 18 non-purgeable volatile organic compounds of which nine have no EPA-approved method. These polar liquids were spiked into distilled water at 1- to 100-ppm levels and analyzed in triplicate at seven concentration levels using a fused-silica capillary column interfaced to an ion trap MS. Using internal standardization, the relative response factors and relative retention times for the 18 compounds were determined. Duplicate data were collected using on-column and splitless injectors. Accuracy and method detection limits (MDLs) were calculated from 10 replicate injections of 2-ppm standards. For splitless injection, the average relative standard deviation for the compounds was 19% and the average MDL was 88 ppb; for on-column injection, the relative values were 13% and 800 ppb. Agreement with EPA-established criteria for 4-bromofluorobenzene will also be shown. Data from the EMSL-LV Analytical Sciences Division are presented to show conditions and limitations involving method parameters, such as column type, injection volume, and spectral quality.