Ways in which a high school principal implemented a shared decision-making structure into his school are described in this case study. Two research questions are explored: the identification of the principal's school improvement agenda; and how he improved his school. Methodology involved interviews with the principal and teachers, as well as administration of a school norm checklist to teachers. The survey response rate for all four case studies was 91 percent. The principal's perceptions of his school improvement strategies were characterized by two themes: judicious decision making; and gradual implementation of teacher participation in decision making. Teachers' perceptions of their principal's strategies were congruent with his stated agenda in the following areas: high standards for students and teachers; an emphasis on instructional time; shared decision making; and professional development. Three tables and two figures are included. (24 references) (LMI)