The author cites conditions for error within schools as one major reason for limited effectiveness of instructional supervision. The ongoing diagnostic process of identifying conditions that reduce the effectiveness of supervision is termed organizational learning. The importance of involving the entire school system is emphasized, and the initial participation of senior level administrators is stressed. It is explained that data collected at each level of the system could be used to construct an organizational map identifying conditions for error and the effects on the school's social system. Feedback and potential solutions are then considered. Conditions for implementing organizational learning are summarized. The author offers an example of such organizational learning undertaken at a residential school for handicapped students. Results of the efforts at the school are said to have increased the effectiveness of supervision by requiring administrators to focus on their own behavior first. (CL)