In the last two decades, Ireland has progressed to a multi-track system for supporting autistic children and young people (CYP) in school settings. Some have suggested that inclusion in Ireland is at a crossroads with the continued expansion of special classes in mainstream settings at the centre of debate. Despite the increasing recognition of the importance of including the voices of all children regarding matters that affect their lives, research exploring the experiences of autistic CYP remains sparse, with the continued prioritisation of the perspectives of adult stakeholders. The researcher conducted both a narrative and systematic examination of current literature which found that autistic student experiences in mainstream second-level schools are complex and often challenging. Nineteen autistic students participated in a qualitative, phenomenological research study. The researcher adopted an innovative methodology, influenced by Universal Design for Learning and Student Voice frameworks which involved the creation of transparent and accessible research materials. Semi-structured interviews were adapted alongside elicitation tools such as diamond ranking, pupil drawings and visual cues to support participation and engagement. Multiple site visits were conducted to maximise student engagement and forty�eight interviews were conducted in total. The data were analysed using Reflective Thematic Analysis. Students identified a range of barriers and facilitators to their inclusion across various aspects of school life. Facilitators included friendships, positive student-teacher relationships, whole school understanding of autism, and access to safe, quiet spaces. Challenges identified included the sensory environment, experiencing bullying and stigma, an inflexible curriculum, and a lack for support for key transitions. Students also offered their perspectives regarding important autism related topics including well-being, identity, masking, and disclosure. This study provides a novel insight into the lived experiences of autistic students enrolled in mainstream second-level schools in Ireland. The findings are critical in addressing both a methodological and knowledge gap in the current research literature. The current study has the potential to inform future research, practice and policy, by centring the voices of autistic students and promoting best practices for conducting research with this cohort.