Although much education supervision literature seems applicable to supervisory practice at all schooling levels, each level has differences, as well as similarities, regarding supervisory context, supervisor roles and responsibilities, and supervisor and staff member characteristics. This paper describes and compares supervisors and supervision at the early childhood, elementary, and secondary levels, focusing on the day care director, the elementary principal, and the high school principal. Generalizations are then made that have implications for the recruitment, training, and support of supervisors. First, supervision is not valued at any level; in each case, the director/principal lacks adequate support to supervise staff appropriately. Second, supervision is only one aspect of a broader, all-encompassing role associated with being an educational program head. Third, as organizations become larger, supervision becomes less personal and more formal. Fourth, when moving from preschool settings to high schools, supervisory focus shifts from the child, to the teacher, to the subject and the teacher. Fifth, at each level there is a racial and gender imbalance among supervisors, teachers, and children. Sixth, at the day care and elementary levels, the director/principal's educational background and work experience may not match students' ages. Seventh, staff development is a crucial supervisor role at each level. Finally, directors and principals need more training in supervising noninstructional staff. Clearly, directors and principals' supervisory roles and working conditions do not enable regular staff supervision to occur in a thoughtful, meaningful manner. (25 references) (MLH)