In this review paper we present some research results on the use of conjugated polymers for electroluminescence (EL). In the introduction a comparison is made between the relative potential for conjugated polymers and the various other classes of EL material. We then discuss the structure and operation of conjugated polymer based devices and the progress that has been made in enhancing their efficiency. The importance of obtaining balanced carrier injection and transport is demonstrated by the effectiveness of multilayer heterostructure devices. A discussion of the likely non-radiative decay processes competing with EL is possible on the basis of earlier studies of the photophysics of the polymer emissive layers. Specific examples of molecular level polymer engineering in copolymer systems are presented and their use to allow lateral patterning of a film is considered. The range of colours available through tuning the polymer π-π* energy gap is reported and a discussion of possible future directions for research is given. © 1993.