An electrochemical technique has been employed to study the ionization of the iodine complexes of (C6H5)3N and (C6H5)3P. Comparison of the results with a previous study indicates that, at high iodine concentrations, the phosphorus compound behaves like (C6H5)3As and (C6H5)3Sb with the formation of a doubly charged ionic species, (C6H5)3PI22+. The nitrogen compound resembles pyridine in its behavior. Chemical shift data on the (C6H5)3P–I2 system using 31P NMR indicates the presence of additional equilibrium processes.