A rapid and sensitive differential-pulse adsorptive stripping voltammetric method, based on the formation of an electroactive complex between aluminium(II1) and 8hydroxyquinoline (HGx), is presented for the determination of trace levels of alumhrium. The complex showed an oxidative peak potential at + 0.876 V vs. Ag/AgCl (saturated KCl) at a glassy carbon (GC) electrode in aqueous ammonium acetate (0.024 M, pH 6.8). A good linear relationship between the peak current and Al(III) concentration in the ranges 4.00 X 10-s-5.00 X 10e6 and 8.00 X 10-6-4.00 x 10e5 M were observed. In the lower Al(III) concentration region, the anodic peak was the result of the stripping of the adsorbed Al(III)_HGx complex, whereas in the higher concentration range, the diffusional oxidation current of the solution species predominated. A surface saturation region was observed from 5.00 x lO-'j to 8.08 x 10m6 M Al(II1). Relatively few interferences were found and these were easily masked. The detection limit for Al(II1) for this method is 1.00 X lo-' M and ten determinations of Al(II1) at 1.00 X 10e7 M gave a relative standard deviation of 6.2%. The method was employed in the analysis of Al(II1) in a US Environmental Protection Agency water pollution quality control sample (WP 386) and excellent agreement with the certified value was obtained.