Solvolysis of triphenylvinyl-2-14C triflate was carried out in HOAc, 97% HCOOH, or CF3COOH. The reaction products showed rearrangements of the 14C-label from C-2 to C-1 averaging about 6.7, 7.7, and 27.0%, respectively, for the acetolysis, formolysis, and trifluoroacetolysis. The presence of the conjugate base of the solvent, added as the sodium salt, did not affect the extent of rearrangement. It is suggested that the 1,2-phenyl shift across the double bond of the triphenylvinyl cation takes place during the ion-pair stage and that the extent of rearrangement is related to the lifetime of the ion-pair and the nucleophilicity of the solvent.