Evaluation by objectives casts the principal in a quite different role than in the traditional rating type of evaluation. Inspectional contacts with teachers are deemphasized; partnership interactions are greatly increased. So changed is the role of the principal that one of the critical aspects is to gain an understanding of the full implications involved. Those principals who have participated in traditional modes of rating and supervision frequently have some difficulty in clearly visualizing how performance evaluation alters relationships and conditions. Perhaps one of the confusing aspects is that some of the highly visible procedures are similar under traditional rating systems and evaluation by objectives.