Background. Oximes have been extensively used as antidotes and decontaminants. Micelles and vesicles can be used as catalysts and drug transport agents. Here we describe the reaction of p-Nitrophenyl diphenyl phosphate (pNPDPP) with: acetophenoxime (I); 10-phenyl-10-hydroxyiminodecanoic acid (II); 4-(9-carboxynonanyl)-1-(9-carboxy-1-hydroyimino nonanyl) benzene (III); N-dodecylpyridinium chloride (IV); N-methylpyridinium2-aldoxime chloride (V), in the presence of cationic and zwitterionic micelles, hexadecyltrimethylammonium chloride, CTAC and  N-Hexadecyl-N,N–dimethyl-1-propanesulfate (HPS), respectively,  and cationic vesicles of dioctadecyldimethylammonium, DODAC. Methods. The apparent pK_a, pK_ap, the second order rate constant of oximolysis in micelles or vesicles, k_m, and the observed rate constants for pNPDPP oximolysis, k_y, of the oximes were determined spectrophotometrically at constant pH using varying amphiphilic concentrations. The results were analyzed using the pseudo-phase theory with explicit consideration of ion exchange, PPIE, as described previously by our group. Results and Conclusion. The second order rate constant for (uncatalyzed) oximolysis of pNPDPP, for a series of oximes, was ca. 6.5 M^-1 min^-1 (I, II and III) and 2.77 M^-1 min^-1 (IV and V). From the maximum value of k_y  in micelles and vesicles, k_ymax, and the value of k_y in water, k_yw, at the same pH, the maximum acceleration factor, AF, for each amphiphilic was calculated (AF= k_ymax/k_yw). The amphiphiles catalyzed the oximolysis of pNPDPP and the values of AF (and k_m) were ca 6x10⁴ (32), 9x10⁶ (80) and 5x10⁶ (63) for the reactions of oxime IV with CTAC, DODAC and HPS, respectively. Quantitative analysis of the amphiphilic concentration dependence of rates demonstrated that the considerable rate increase produced by micelles and vesicles on the rate of oximolysis (up to 9x10⁶ fold) is partly due to reagent concentration in the aggregate as well as effects on the pK_a of the nucleophiles and, more importantly, that these aggregates catalyze the oximolysis reaction.