The synthesis of a new liquid crystalline block copolymer consisting of a polystyrene block and a side-chain liquid crystalline siloxane block is reported. The synthetic approach described is based on the anionic polymerization of styrene and cyclic trimethyltrivinyltrisiloxane monomers, followed by functionalization of the siloxane block with side chain mesogens. The siloxane block has a T-g well below 25 degrees C and is designed to exhibit a chiral smectic C* phase at room temperature. These block copolymers are the first sidechain liquid crystalline block copolymers which contain both a high T-g glassy block and a low T-g liquid crystalline block.