During the past ten years in the UK there has been a considerable increase in the number of teaching assistants (TAs) appointed to work alongside teachers in schools. A significant number of these colleagues are appointed to support pupils with special educational needs (SEN), including those with social, emotional and behavioural difficulties (SEBD). This paper reports on the ways in which the role of the teaching assistant in supporting pupils with SEBD has been developed in schools for pupils aged 7-11 years in one English Local Education Authority (LEA). It suggests that there are several models of support emerging and that the role of the teaching assistant is perceived as crucial to the effective inclusion of pupils with SEBD in mainstream classrooms. (Contains 16 tables.)