From the seismic tomographic models, we estimate the offset between the geographic pole and the main inertial axis. This offset, which is large for a static Earth, is drastically reduced when the dynamical behavior of the mantle is taken into account. For a mantle stratification with a viscosity increase by a factor of about 50, this offset is comparable to what can be estimated on the basis of remanent post-glacial depression. We also discuss the rate of polar drift induced by both internal mass heterogeneities and Pleistocenic deglaciation. Contributions from internal sources and ice-sheets disintegration are consistent with the observed secular trend. For high viscosity contrasts, our results are quite insensitive to the phase transition or chemical nature of the upper-lower mantle interface. This study shows that there is no contradiction between the tomographic models of the Earth and their implications for the rotation stability of our planet; our findings also agree with recent analyses of paleomagnetic data. ¿ American Geophysical Union 1990