AbstractWell defined oligo(arylenevinylene)s were prepared by Pd‐catalyzed coupling of dibromoarenes and styrenes. The mixing behavior of these oligo(arylenevinylene)s with polymers is significantly influenced by the structure of the oligo(arylenevinylene)s. Potential consequences for optical properties are discussed. Segmented polymers with arylenevinylene segments in the main chain are presented and discussed in detail. Light‐emitting thermotropic polymers were obtained with modified distyrylbenzene segments in the main chain. These thermotropic light‐emitting polymers show polarized photoluminescence on orientation on rubbed polyimide substrates. Light‐emitting amorphous polymers with high fluorophore concentrations and high glass transition temperatures were obtained by polymers with arylenevinylene segments in the sid