Australian education policies aspire to meet the unique needs of all students including those from linguistically diverse backgrounds; however, a first step in achieving this aim is clear identification of such students. Many children from previous migrant families and new arrivals to Australia come from homes where at least one parent speaks a language other than English. This exploratory research utilises survey and interview responses from students and staff in five Queensland state high schools. Results showed that 79.5% of the 2,484 students surveyed were from English-only homes with only 10.5% classified as having English as Another Language/Dialect. The remaining 10% were also from bi/multilingual homes. While early identification of bi/multilingual students allows for appropriate assessment and strategic support, staff responses highlighted limited preservice training and/or understanding of how to support these students. Only 4.7% of staff surveyed had received any academic training, and 10.4% professional development, about teaching students from diverse backgrounds who, in the surveyed schools, accounted for 20.5% of the student cohort.