This paper presents the findings of a comparative study using data from questionnaire surveys carried out in England (n=57) and Ireland (n=72). The researchers examine how teachers and teaching assistants who are currently teaching pupils with dyslexia in primary schools describe dyslexia and what may have influenced their conceptualisation. The paper examines teachers' responses both in terms of how they view their pupils presenting difficulties in the classroom, and how far they link these to underlying differences in cognitive processing. The researchers suggest ways in which this might influence their teaching in terms of methodology. Findings have been mapped to the Morton and Frith causal modelling framework. The implications of these findings for the training and support of teachers are discussed in the light of recent national initiatives to improve the teaching of dyslexic pupils in both countries.