There is increasing interest in the role of peers in facilitating the social interaction of pupils with ASD through Peer-mediated Interventions (PMI). A systematic literature review was conducted to provide an overview of methods used to evaluate the impact of PMI and provide examples of innovative practice. Four databases were searched. Following application of inclusion and exclusion criteria and coding of studies, 10 were included in the final review. The review found that measuring the outcome of PMI at the level of target pupils has been a focus, with less attention given to exploring experiences of participants; impact on peers and implementation of PMI within an educational context.An innovative PMI was implemented within a mainstream primary school to promote the social inclusion of a Year 3 male pupil with ASD, with his class and five peers. Key elements of the PMI included development of the programme with school staff, whole class awareness raising and a small group peer network. The intervention was evaluated through structured playground observations of pupil-peer interaction, interviews with the target pupil and school staff and a peer focus group. Findings indicated that this small-scale PMI had a positive impact at the level of the target pupil and peers. Key factors facilitating the implementation of this intervention within a school context were also identified. A structured dissemination strategy that involved consultation activities with key stakeholders explored the refinement of an ecologically valid and feasible model for delivery in mainstream schools. Future considerations in developing the intervention framework include; refining elements of the programme based on feedback from key stakeholders and trialling the delivery of the intervention by school staff trained in the programme. Implications for Educational Psychologists (EPs) in the development and delivery of the intervention are discussed.