The ionic conductivity of well-annealed crystals of rubidium chloride and of RbCl doped with Sr2+or S2-ions has been measured, using an automated system, over a wide range of temperature, generally from 960 K until precipitation occurred. Conductivity data were analyzed using a multiparameter non-linear least squares fitting program. The defect model used allowed for the possibility of Frenkel defects on both cation and anion sub-lattices and the association of cation vacancies with divalent cations and of anion vacancies with divalent anions. Data for the individual crystals were analyzed separately and a consistent set of defect parameters were obtained.