The aim of this study was to determine whether it was possible to predict therapy gain from participants' performance on background tests of language and cognitive ability. To do this, we amalgamated the assessment and therapy results from 33 people with aphasia following cerebral vascular accident (CVA), all of whom had received the same anomia therapy (based on progressive phonemic and orthographic cueing). Previous studies with smaller numbers of participants had found a possible relationship between anomia therapy performance and some language and cognitive assessments. Because this study had access to a larger data set than previous studies, we were able to replicate the previous findings and also to verify two overarching factors which were predictive of therapy gain: a cognitive factor and a phonological factor. The status of these two domains was able to predict both immediate and longer-term therapy gain. Pre-treatment naming ability also predicted gain after the anomia therapy. When combined, both cognitive and language (naming or phonological) skills were found to be independent predictors of therapy outcome.