This paper reports on findings of a research study on the district-level control of principals in 12 effective school districts in California. Primary research objectives were (1) to expand knowledge on the nature of administrative control, (2) to develop a better understanding of the processes and activities in effective school districts, and (3) to study the role of the superintendent in providing leadership in coordinating district and school activities and in promoting effectiveness. Other objectives were to examine differences among patterns of control uncovered in these effective districts and in studies of other school districts, as well as to compare types of control used across districts within the sample. Issues studied included the following: the hiring of new principals from within and from outside the district; the use of formal administrator internship programs; factors superintendents look for in hiring principals; supervision and evaluation of principals; school visitation by superintendents; principal participation in staff development programs; rewards and sanctions; goals; resource allocation; behavior control and monitoring; and technological specifications. The paper concludes with a discussion of patterns and themes that emerged from the study. Appended are 1 figure, 1 table, 13 notes, and 5 pages of references. (IW)