A new, very stable dithiocarbamate, bis(n-butyl-2-naphthylmethyldithiocarbamate) zinc(II), has been synthesized and its use in trace metal determination by high-performance liquid chromatography (h.p.l.c.) has been investigated. Metal complexes of this ligand are thermodynamically stable and kinetically inert at the 1 × 10-8 M level. Various metal complexes including nickel(II), iron(III), copper(II), mercury(II), and cobalt(II) have been "baseline" separated by nonpolar stationary-phase h.p.l.c. The detection limits are about 1-2 ng with a variable-wavelength absorbance detector.