The architecture of polymer light-emitting diodes (LEDs) consists of a thin film of luminescent conjugated polymer sandwiched between two contacts. The difficulty of working with low-workfunction, electron-injecting metals such as calcium, which are generally considered necessary for high luminescence efficiency, has led to relatively high-workfunction metals such as aluminum being examined for their potential as cathode materials. The performance enhancement produced by blending the electroluminescent polymer with a specific class of surfactant molecules is reported.