Circumstances in today's schools are requiring a rethinking of pedagogical approaches so that equitable learning opportunities are provided to all students. This small-scale, qualitative Australian study reports how some teachers and school leaders viewed differentiated instruction (DI) being applied in their secondary campus to address diverse abilities and needs. Individual semi-structured interviews were conducted using Zoom. The analysis of data identified three themes related to DI: understandings, practices, and concerns. Findings showed that all participants understood many of the important elements of DI. Teachers reported using several well-known DI strategies, with experienced teachers applying a more considered approach. Teachers raised concerns about limited time for planning and instruction while school leaders expressed concerns about the adjustment of assessment tasks and feedback on progress to individual students. These findings provide starting points for more in-depth investigations at secondary schools. Implications linked to teacher preparation and administrative support in schools are presented.