A liquid crystal device comprises a first cell wall and a second cell wall enclosing a layer of liquid crystal material. The device has electrodes for applying an electric field across at least some of the liquid crystal material, and a surface alignment structure on a region of a substantially planar inner surface of at least the first cell wall. The alignment structure induces the liquid crystal material to adopt a desired alignment in an azimuthal plane. The surface alignment structure comprises a two dimensional array of microstructures which are shaped and oriented to produce the desired alignment. Each microstructure has no plane of symmetry orthogonal to the azimuthal plane and to said planar inner surface.