trans-4-[4(dimethyl-amino)] stilbazolium p-toluenesulfonate, a well-known organic second-order nonlinear optical material, is described. The DAST nanocrystals were oriented in an acrylate monomer by an applied magnetic field and then immobilized by UV-curing. The optical anisotropy of the absorption and refractive index of the obtained solid-which is odorless, transparent, heat resistant, insoluble, and soft, like rubber-is shown to be easily controlled by the magnetic field.