ABSTRACTThe function of rapid perceptual learning for speech in adult listeners is poorly understood. On the one hand, perceptual learning of speech results in rapid and long-lasting improvements in the perception of many types of distorted and degraded speech signals. On the other hand, this learning is highly specific to stimuli that were encountered during its acquisition. Therefore, it is unclear whether past perceptual learning could support future speech perception under ecological conditions. Here, we hypothesize that rapid perceptual learning is a resource that is recruited when new speech challenges are encountered and used to support perception under those specific conditions. We review three lines of evidence related to aspects of this hypothesis – about the specificity of learning, the general nature of associations between rapid perceptual learning and speech perception and rapid perceptual-learning in populations with poor perception under adverse conditions.