S. John Davis served as superintendent of public instruction for the Commonwealth of Virginia from 1979 to 1990. Dr. Davis worked for three governors--John N. Dalton, Charles S. Robb, and Gerald L. Baliles. His tenure in office marked an important era of innovation and change in Virginia's educational history. Davis' state superintendency is first analyzed by a description of the developmental influences which shaped his career. These influences include personal, educational, professional, and historical elements. The second factors of analysis include the institutional limits which shape the work of a state superintendent. A review of the roles of the executive branch, the legislature, the board of education, the department of education, local school divisions, education interest groups, and the Constitution and Code of Virginia make up this aspect of the study. In the third component of analysis five career themes are identified as continually evolving elements in Davis' work. The five themes are politics, funding, educational initiatives, accountability, and management philosophy and style. These variables yield a typology for describing state superintendents of public instruction. S. John Davis' state superintendency is used to explore and test the validity of the model. / Ed. D.