while the occupation of teacher assistant has become rooted in the ontario school system no research exists concerning the roles these teacher assistants perform in ontario. there is also a paucity of research which examines teacher assistant roles from the point of view of teacher assistants themselves. this research investigated the roles of teacher assistants in two elementary school special education classrooms in ontario. qualitative methods were used to gain an insider’s view of what teacher assistants do in the classroom. these methods included interviews with teacher assistants, teachers, principals and a superintendent as well as observations of teacher assistants and teachers working together in the classroom and document analysis of the site school board teacher assistant job description and relevant ontario teachers’ federation documents. based on the data a conceptual model of the roles of the teacher assistant was developed. this model consisted of two categories of roles. category i was called working with children and consisted of five roles: instructor, behaviour manager, observer, caregiver and team player. category ii was called non-contact with children and consisted of two roles: technician and clerk. implications of this research include the development of curriculum for preservice and inservice programs for teacher assistants as well as augmenting curriculum in teacher preservice special education training in order to address how to fully utilize the teacher assistants in the classroom. further research is recommended to investigate the caregiver role in greater depth and to examine the relationship between the roles of the teacher and the teacher assistant.