Measurements of magnetic viscosity in equiaxed isotropic and anisotropic Alcomax III specimens have been made; the anisotropy was induced by cooling the material, from the single phase region, in a magnetic field of 4000 Oe. The results are discussed in terms of the concept of the thermal activation of irreversible domain boundary wall movements. Comparisons of the results of measurements on anisotropic and isotropic specimens are in reasonable agreement with theoretical predictions.