Teacher–student relationships develop from real-time teacher–student interactions. These real-time interactions can be characterized by interpersonal content, structure, and complementarity. We studied how teacher–student interactions measured in terms of these characteristics differed for two teachers with distinct teacher–student relationships. A computer joystick device enabled us to measure teacher and student interpersonal behavior as a two-dimensional construct, a blend of Agency and Communion. Our results indicated that interpersonal content and complementarity discriminated between teachers, and that interpersonal structure did not. Measuring these characteristics seems promising to understand differences in teacher–student relationships.