Researchers who view schools as cultural organizations have tended to assume that they are monocultural entities. This paper presents a view of complex secondary schools as multicultural organizations. It discusses findings of a year-long study that examined the professional culture within two high schools in Washington State as each attempted to implement several reform objectives, including new master schedules. The study used the model of organizational subcultural analysis developed by Bloor and Dawson (1994) to identify and describe the subcultures and their various interactions throughout the year. Data sources included social artifacts, indepth interviews with at least half of the teaching and administrative staff in each school, and observation. The results suggest that the subcultural level, along with the individual and organizational levels, may also be critical for successful implementation of reform. There is a need for continuous "reframing" of a change according to the values of a specific professional subculture. The paper describes the ways in which different professional subcultures sought to strengthen their positions in order to realize their particular ideological visions. In most cases members of the less extreme, or "orthogonal" groups were most successful in this effort, serving as mediators between the dominant and dissenting subcultures. Finally, the findings brought to light the pain experienced by highly visionary reformers when their missions fail or are ridiculed. (Contains 49 references.) (LMI)