This paper describes a field evaluation of a tandem mass spectrometer (TAGA) for use in measuring turbulence fluxes of trace gases. Measurements were made over a two-day period in a fallow farm field west of Columbus, OH. The results show that for weakly adsorbing species such as acetone, the effective time constant for the TAGA is < 0.1 s, and the device can be used for eddy correlation flux measurements with little need for corrections. The effective time constant is longer for adsorbing species, such as ammonia, but spectral corrections can permit flux estimates fur these species as well. This paper presents the first reported measurements of fluxes of acetone, formic acid, and ammonia using the eddy correlation technique. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.