The expectation that teachers’ professional practice will effectively accommodate diversity in their classrooms has drawn attention to issues that impact teachers’ ability to manage these challenges. This paper reports on the implications out-of-field teaching practices have for the effective management of diversity in classroom contexts. The qualitative investigation involved semi-structured interviews, classroom observations and document analysis from 48 participants and seven schools. A new context-conscious understanding development theory underpins the investigation. The results and key findings demonstrate that the out-of-field phenomenon has significant implications for students’ learning needs. The paper concludes with reflections on strategies for the more effective management of diverse learning environments when the out-of-field phenomenon is in play.