This paper describes Hilltop Junior High School's initial experience with interdisciplinary teaming, an arrangement whereby teachers from different disciplines systematically plan curricular experiences for a common group of students. The innovation began with the appointment of a new principal who advocated teaming as the basic unit of middle school organization. Thus the site provided an opportunity to observe the processes and effects of organizational and curricular change as they occurred. In order to understand the emergent expectations, behaviors, interactions, and their meanings for participants as the innovation took shape, the researchers observed weekly planning meetings of the three teams, interviewed teachers and administrators, and reviewed relevant documents throughout one school year. Following an introduction and rationale for the study and a description of the research methods, the paper describes the development of teaming, the functioning of the three teams, and the foci of teachers' discussions during planning meetings. These events are then discussed with respect to the redistribution of authority, loose coupling, staff recruitment, rewards, structural lag, and work load. Several implications for curricular decision making and staff development are then explored. The paper concludes with five working hypotheses which provide direction for additional investigations. References are included. (Author/TE)