Rates of acetolysis of 2-aryl-2-methylpropyl p-bromobenzenesulfonates were determined for an extended series of substituents. The substituent effect can be described accurately in terms of our LArSR relationship (Yukawa-Tsuno Equation), giving an r value of 0.57. The correlation result can be reasonably accounted for on the basis of the accepted mechanism of this reaction, involving a rate-determining