The study investigated cognitive deficits associated with dyslexia and familial risk of dyslexia (endophenotypes) by comparing children from families with and without a history of dyslexia. Eighty-eight school-aged children were assessed on measures of phonology, language and rapid automatized naming. A series of regression analyses with family risk and dyslexia status as predictors indicated that word recall, morphology, and rapid automatized naming were associated with the deficit, whereas the two phonological measures (phoneme awareness and nonword repetition) were associated with both literacy deficits and family risk, suggesting that the phonological deficit is an endophenotype of dyslexia. Whereas the association with familial risk was similar for the two phonological measures, they differed in their relation to dyslexia status: Phoneme awareness showed a stronger association with dyslexia than risk status, whereas nonword repetition was more strongly related to the risk. The data are interpreted within the framework of multiple deficit models of dyslexia.