Imagine the impact on your daily and professional life of not being able to do what you are doing now; extracting meaning from language. This is a fate and frustration that faces many people with aphasia post stroke, in neurodegenerative disease or other forms of brain damage. The clinical demand and potential for efficacious interventions for aphasia are both clear. Aphasia following stroke, for example, is common (around 1/3 in the acute phase: 1). Progressive language impairments are a core aspect of the symptom complex in Alzheimer’s disease, over and above the increasingly recognised progressive aphasias 2 3. Speech and language therapies for aphasia can be effective 4 5 though there is a need to understand the mechanisms and the bases of the considerable individual differences in therapy effect.