In this article, I propose collaborative mentorship (CM) as a mentoring approach to support and sustain teachers in diversity and equity education. CM is theorized as a mentoring relationship grounded in critical dialog between mentor and mentee. Drawing on research conducted in a culturally, racially, linguistically, and socially diverse secondary school in Southern Ontario, Canada, this article examines tensions teachers experience with equity and diversity and the knowledge base necessary for such a mentoring approach. As the schools become more diverse, it is vital that teachers seek out new approaches that respond to the changing social contexts. The findings of my research have implications for teacher professional development and teacher training in discovering new ways to support in diverse classrooms.