This study explores the experiences of primary teachers with utilising the Aistear Early Childhood Education Curriculum to support inclusive education for autistic children with mainstream primary schools. Ireland has moved increasingly in recent decades towards providing education for autistic pupils within mainstream school settings, with 86% of such students being enrolled in mainstream schools and classes in 2016 according to the NCSE. Autistic pupils enrolled in early intervention classes are commonly supported using the Aistear curriculum, a holistic play focused early childhood education curriculum. However, there is little research exploring the experiences of primary teachers with implementing this curriculum to support inclusion within mainstream classes for autistic children, nor what supports or access to professional development are available. Interviews were conducted with 10 primary school teachers who have worked with autistic pupils using the Aistear curriculum. The interviews were conducted using Zoom and were between 30 and 60 minutes in duration. Thematic analysis (Braun & Clarke, 2006) was used to analyse the data, with two themes emerging. The first was “Using Aistear to Support Inclusion” which had two sub-themes, “Tailoring the Curriculum” and “Tailoring the Environment”. The second theme was “Aistear and Whole School Approaches”. Findings show that, while participating teachers were often positive about using the Aistear framework, they pointed to the lack of support and guidance provided within the Aistear curriculum to inform their teaching and differentiating to support inclusion. This had implications for teacher collaboration and use of the Aistear curriculum in primary school settings.