Systems lacking inversion symmetry, such as selected three-dimensional compounds,multilayers and surfaces support Dzyaloshinsky–Moriya (DM) spin–orbit interactions. Inrecent years DM interactions have attracted great interest, because they maystabilize magnetic structures with a unique chirality and non-trivial topology. Theinherent coupling between the various properties provided by DM interactions ispotentially relevant for a variety of applications including, for instance, multiferroicand spintronic devices. The, perhaps, most extensively studied material in whichDM interactions are important is the cubic B20 compound MnSi. We review themagnetic field and pressure dependence of the magnetic properties of MnSi. Atambient pressure this material displays helical order. Under hydrostatic pressure anon-Fermi liquid state emerges, where a partial magnetic order, reminiscent of liquidcrystals, is observed in a small pocket. Recent experiments strongly suggest thatthe non-Fermi liquid state is not due to quantum criticality. Instead it may bethe signature of spin textures and spin excitations with a non-trivial topology.