This article explores the process by which children attending mainstream UK primary schools can achieve social inclusion. It presents the findings from a systematic literature review, followed by empirical research, exploring the concept of social inclusion with particular regard to the experiences of pupils identified with SEND. The article draws upon research conducted for the author's doctoral study, which explored management of the role of Teaching Assistants on the social inclusion of pupils identified with SEND in mainstream primary schools. Reviewing relevant literature has informed the presentation of two researcher-devised models, tentatively depicting the process of social inclusion for pupils identified with SEND in mainstream primary communities, as 'fuzzy generalizations', to inform future research. Firstly, an 'ideal' model of social inclusion is presented, highlighting the likely process by which pupils may achieve the end goal of social inclusion: participation. Secondly, a 'current' model of social inclusion is presented, which draws upon the empirical research conducted in three mainstream primary contexts for the author's doctoral study. The two models highlight the frequent disparity between the 'ideal' goal of social inclusion and the current outcome of the process of social inclusion for many pupils identified with SEND in mainstream primary contexts.