Spin-orbit coupling gives rise in magnetic solids to a large number of effects that are at the
same time of great scientific as well as technological interest. As examples for this, results of
recent investigations based on a fully relativistic Dirac formalism on the magneto-crystalline
anisotropy, angle resolved photo emission (ARPES) and the Gilbert damping parameter will
be presented. To achieve a coherent treatment of the magnetic anisotropy the Breit
interaction was recently included in the underlying Hamiltonian. In this way the spin-orbit
induced part of the anisotropy energy as well as the dipolar shape anisotropy are treated on
the same quantum mechanical footing. As will be demonstrated for various layered magnetic
systems, this approach gives results very similar to the common classical approximation to
the shape anisotropy. The magnetization dynamics in magnetic materials is conventionally
described in a phenomenological way on the basis of the Landau-Lifshitz-Gilbert (LLG)
equation, with the Gilbert damping parameter ? representing damping processes. Results of
ab-initio calculations of the Gilbert damping parameter and its temperature dependence will
be presented and discussed for a number of transition metal systems. Another field that is
strongly influenced by spin-orbit coupling is electron spectroscopy where it gives rise to
various dichroic and magneto-optical effects. Results of corresponding studies on spin and
angle resolved photo emission will be presented that are based on the one-step model of
photo emission. As it will be demonstrated, ARPES is especially suited to probe the role of
spin-orbit coupling for the electronic structure of Rashba-type systems or topological
insulators.