  Crystallographic lattice defects strongly influence dynamical properties of
magnetic materials at both microscopic and macroscopic length scales. A
multi-scale approach to magnetisation dynamics, which is presented in this
paper, accurately captures such effects. The method is illustrated using
examples of systems with localized, non-trivial topological properties, e.g. in
the form of skyrmions and chiral domain walls that interact with lattice
dislocations. Technical aspects of the methodology involve multi-scale
magnetisation dynamics that connects atomistic and continuum descriptions. The
technique is capable of solving the Landau-Lifshitz-Gilbert equations
efficiently in two regions of a magnetic material --- the mesoscopic and the
atomistic regions, which are coupled in a seamless way. It is demonstrated that
this methodology allows simulating realistically-sized magnetic skyrmions
interacting with material defects and novel physical effects, uncovered using
this theoretical methodology, are described.
