As a result of their high contact time with children, particularly children identified with special educational needs, it is widely acknowledged that teaching assistants (TAs) have great influence on pupils' education (Balshaw). However, recent research into the impact of TAs on pupils' learning has questioned TAs' usefulness in improving pupils' learning (Blatchford, Bassett and Brown; Higgins). This paper argues that TAs' influence on pupils' education has not yet been researched effectively. Previous research has primarily focused on determining TAs' influence on pupils' achievement in terms of academic outcomes and has neglected to explore social outcomes. Two interconnected literature bases are reviewed in this paper; the current research exploring TAs' role and influence on pupils' learning is first explored, followed by a critical discussion of the literature regarding the process of social inclusion in mainstream primary schools. This paper concludes that for TAs' influence on pupils' learning to be effectively researched, TAs' influence on the process of social inclusion must be researched within mainstream primary schools.