Developmental Language Disorder (DLD) is a common, lifelong disorder affecting around two students in every classroom. DLD is a persistent disorder of language, with no known cause, and can present in subtle ways that, without sufficient knowledge of its characteristics and educational impacts, can be difficult to distinguish from other common disabilities. As in many other countries around the world, Australian students with a disability, including those with DLD, are entitled to reasonable adjustments to enable them to access education on the same basis as students without disability. However, the often "hidden" nature of DLD often means that these students are regularly not identified or appropriately supported by their teachers. This is problematic, given the responsibility of educators to ensure that students with DLD are not treated unfairly or marginalised due to their disability. Support can take place though the design and implementation of adjustments to ensure these students can gain access and participate in education on the same basis as their peers who do not have a disability. To meet the requirements of Australian legislation, schools and teachers need to understand a students’ profile of language skills, as well as the language demands of the environment, to make a professional determination as to the reasonable adjustments required.This study addressed the research question: What do teachers know about the (i) learner characteristics and (ii) educational impacts of Developmental Language Disorder (DLD)? We drew on previous research conducted in the UK to develop an online survey instrument appropriate for use with teachers in Queensland. The final survey instrument investigated the depth of classroom teachers’ knowledge of DLD and consisted of 28 questions. The final sample comprised 262 teachers of which 177 were primary school teachers and 85 were secondary school teachers. Participants’ ability to identify the characteristics of DLD was assessed in three ways: first, through a self-rated knowledge question, followed by two multiple-choice knowledge demonstration tasks. This research revealed a mismatch between participants’ self-rated and demonstrated knowledge. In this presentation, we will discuss these findings and the implications of this research for teachers’ capacity to successfully include students with DLD as required by anti-discrimination legislation, professional standards and inclusion policies. Finally, we will discuss recommendations for teacher education and professional learning.