Findings of a study that examined the impact of organizational structures for shared decision making on teacher participation are presented in this paper, with attention to the types of issues that were raised and the nature of changes introduced. A longitudinal study was conducted of 12 high schools in 11 states for an average of 17 months per school. Six schools with shared decision-making (SDM) structures were compared with six schools with traditional administrative structures. Data were derived from interviews with a total of 191 administrators, teachers, and school staff--105 from SDM schools and 86 from traditional schools. Findings suggest that the presence of participatory decision-making structures did not necessarily lead to enhanced teacher creativity; in fact, most faculty attempted to slow down the pace of change. Although teachers' morale improved, their influence on decision-making was usually limited within boundaries determined by the principal. However, shared decision making does provide a forum for teacher-administrator interaction and shared knowledge. Two tables are included. (Contains 16 references.) (LMI)