Phonagnosia, the inability to recognize familiar voices, has been studied in brain-damaged patients but no cases due to developmental problems have been reported. Here we describe the case of KH, a 60-year-old active professional woman who reports that she has always experienced severe voice recognition difficulties. Her hearing abilities are normal, and an MRI scan showed no evidence of brain damage in regions associated with voice or auditory perception. To better understand her condition and to assess models of voice and high-level auditory processing, we tested KH on behavioural tasks measuring voice recognition, recognition of vocal emotions, face recognition, speech perception, and processing of environmental sounds and music. KH was impaired on tasks requiring the recognition of famous voices and the learning and recognition of new voices. In contrast, she performed well on nearly all other tasks. Her case is the first report of developmental phonagnosia, and the results suggest that the recognition of a speaker's vocal identity depends on separable mechanisms from those used to recognize other information from the voice or non-vocal auditory stimuli.