This paper gives an account of one aspect of a recent research project that explored dimensions of inclusion in mainstream schools in Ireland. In particular, the working lives of teachers who have specific responsibility for students with disabilities and/or special educational needs (SEN) in mainstream schools were explored. In Ireland, such teachers are known as learning support or resource or SEN (LS/R/SEN) teachers. The nearest UK equivalent role is that of SEN co-ordinator, but the responsibilities of the Irish LS/R/SEN teacher role are not as formalised and tend to vary in different school contexts. A key aspect of the research project was to explore the professional development requirements of these teachers. The contention emerges that the professional development requested by teachers was supportive of traditional practices and that these practices more properly belonged to a medical model-influenced, deficit approach to special education rather than to an inclusive approach to education. As a consequence, it is argued that, instead of responding to gradually evolving change, an alternative, more revolutionary approach to professional development could be adopted to challenge "conventional wisdom" and promote a truly inclusive education system in Ireland.