Dynamical inferences from the dipole anisotropy in the microwave background

The observed peculiar motion with respect to the microwave background may have been generated by inhomogeneities in the Universe on any of a wide range of scales. The theoretical and observational implications of the various possibilities are reviewed, and an explanation in terms of the non-linear collapse of the Local Supercluster in a relatively high density universe seems to be favoured. The critical observations of local kinematics are still, however, highly controversial. (Auth.)