Conductivity measurements on pure and Co2+‐doped K2SO4 crystals indicate that cation vacancies are the dominant charge carriers in the conduction mechanism. From such measurements the energy required for the migration of a cation vacancy and the association energy of the impurity with a potassium vacancy have been obtained. Two loss peaks which are attributed to the orientations of the dipoles formed by the Co2+‐impurity and cation vacancies in the nn and nnn positions, are observed in the dielectric loss studies and support the theory given by Dreyfus. The value of the activation energy for the migration of a cation vacancy, obtained from conductivity measurements agrees reasonably well with that obtained from dielectric loss studies. Copyright © 1973 WILEY‐VCH Verlag GmbH & Co. KGaA