The teacher-student relationship is viewed as integral to successful teaching and learning but, outside of a few exceptions, ethical boundary issues in this relationship have not been explored. The purpose of this study was to examine teachers' perspectives of their relationships with their students as well as how they described and negotiated relationship boundaries. Findings were organised into a typology of 11 categories of boundaries. The balance between demonstrating care while maintaining a healthy, productive level of control in the classroom was a recurring theme when discussing the boundaries. (Contains 2 tables.)