Autistic young people in mainstream schools often experience low levels of peer social support, have negative perceptions of their differences and feel disconnected from their school community. Previous research findings have suggested that encouraging autistic young people to explore autistic culture and spending time with autistic peers may be associated with more positive outcomes. Autism-specific peer support is a framework that may support this process. Thirteen participants (eight male/five female) completed semi-structured interviews, exploring the idea of autism-specific peer support within mainstream schools and the practicalities of how it may work within a school setting. Thematic analysis was applied, and three themes are reported: (1) neurodiversity and an ethos of inclusivity, (2) flexibility and (3) benefits and challenges of embedding peer support in the wider school community. The idea of autism-specific peer support for autistic pupils in mainstream secondary schools was generally positively received. Peer support may provide a unique opportunity for autistic pupils to interact in a natural, comfortable way; share useful strategies; and build their identities. Nevertheless, careful design, training and ongoing support, alongside awareness of the rights, needs and preferences of individual pupils involved are likely to be crucial in ensuring the success of any peer support programme.