In contrast to the numerous treatment studies of spoken language deficits, there have been relatively few studies concerned with the treatment of spelling dis-orders. Among these, there have been only a small number that have targeted specific components of the spelling process. We describe a successful single case treatment study for FME, a woman with acquired dysgraphia, which was conducted within a cognitive neuropsychological framework. Pre-treatment assessment revealed a semantic deficit, impaired access to output orthography and probable additional degradation of the actual representations within the orthographic output lexicon. The treatment study was therefore directed towards relearning spellings by strengthening, and facilitating access to, specific orthographic representations for writing. In order to maximise the functional outcome for FME, treatment was focused on high frequency, irregular words. The treatment programme was carried out in two phases, one without and one with the use of mnemonics, and the results showed a selective training effect with the mnemonics alone. Treatment benefits were item specific but long lasting, and a significant improvement in FME's spelling performance was still evident at 2 months post-treatment. The current study confirms how cognitive neuropsychological theories and methods can be successfully applied to the assessment of acquired spelling impairments, and exemplifies how treatment with carefully designed mnemonics is of benefit if the inability to retrieve orthographic representations for writing is aggravated by a semantic deficit.