Charge transport enhancement layers and structures are provided that may improve the performance of organic devices, specifically organic light emitting devices. A charge transport enhancement layer may include a layer or an inorganic material, metal oxide, halide, and/or alkali disposed between two organic layers, and separated from the cathode by an intervening organic layer. One or more CTELs may be used, such as in an alternating stack of organic and CTEL layers. Surprisingly, it has been found that the use of one or more CTELs arranged in a stack with intervening organic layers may improve the performance of the device even where the layer is not directly adjacent to the cathode.