Compounds (including polymers) for use in hybrid host materials which can be used in electroluminescent devices. The compounds comprise at least one electron-transporting moiety and at least one hole-transporting moiety which are joined by a flexible linker. Hybrid host materials comprising the compounds exhibit stability against phase separation, elevated glass transition temperature, morphological stability against crystallization, and isolation of the electron transporting moiety and hole transporting moiety π-systems.