Preparation of polyelectrolyte multilayer (PEM) films at fluid interfaces between aqueous solutions and liquid crystals is described. The orientation of the liquid crystals is coupled to the presence and organization of the PEM films (see figure). The PEM films can selectively mediate the interactions between solutes and the interfaces of the liquid crystals. PEM films offer a general method to tailor the interfacial properties of liquid crystals for chemical or biological sensing.