The idea of using organic compounds with extended conjugated electron systems for efficient, sustainable, and flexible generation of light has fascinated scientists around the world for nearly three decades now. Within this timeframe, the efficiency, brightness, and stability of organic light-emitting diodes (OLEDs) have improved dramatically. Although OLEDs were initially developed mostly as the active element in emissive displays, the technology has matured to a level that now brings within reach applications in general lighting, a field that poses in many regards much stricter requirements on device performance. General lighting requires OLEDs to generate balanced white emission, produce high brightness levels, and to do so at competitive efficiency when compared to established technology, in particular, fluorescent lamps and conventional LEDs. For many years, a primary focus has been to improve the internal efficiency of OLEDs, i.e., the yield of charge-to-photon conversion. However, in many state-of-the-art devices, this is now achieved with near unity efficiency, mostly thanks to the development of triplet harvesting,1–3 doped charge transport layers,4,5 and efficient charge blocking structures.6 Over the past years, the focus has, therefore, moved toward improving the efficiency of outcoupling, i.e., the fraction of the generated photons that can be extracted from the device into the surrounding air. Despite some good progress, outcoupling remains a major loss channel with well of the photons being extracted from typical OLEDs. Developing efficient and practical concepts for light extraction, in particular for white-emitting OLEDs, thus remains a major challenge in the field.