Pseudo-first-order rate constants (k(obs)) for hydrolysis of ionized N-phthaloylglycine (NPG) at a constant [NaOH] and 30 degrees C increase nearly 50% with an increase in the total concentration of sodium dodecyl sulfate ([SDS](T)) from 0.0 to 0.2 M. The hydrolysis of NPG involves -OH and anionic NPG as the reactants. The increase in [NaBr] from 0.01 to 0.40 M increases k(obs) by nearly 44% at 0.004 M NaOH and 30 degrees C. Pseudo-first-order rate constants (k(obs))increase by nearly 50% with an increase in [KCl] from 0.0 to 0.1 M at 0.003 and 0.004 M NaOH and 30 degrees C. The increase in [SDS](T) from 0.0 to 0.3 M decreases k(obs) for hydrolysis of phthalimide at 0.01 M NaOH and 35 degrees C by nearly 10%. The attempt is also made to explain pseudo-first-order rate constants in terms of interfacial hyroxide ion concentration calculated from the Boltzmann equation using interfacial electrical potential.