Two-step laser mass spectrometry is a novel analytical methodology for ultrasensitive and selective analysis of organic compounds in complicated mixtures. Nonvolatile and thermally labile molecules can be analysed mass spectrometrically, with ppm sensitivity and ca. 100 m spatial resolution. Applications of this method for environmental trace analysis in complex matrices will be explored, in particular: organic deposits in soils and on mineral surfaces, the organic-chemical makeup of aerosol particles, tracing of toxic or carcinogenic compounds in tissue.