This article examines the year-long experience of one fourth grade teacher, Anne, as she learned about comprehension strategy instruction and attempted to integrate the approach in her reading program. The goal of the study was to extend current understanding of the factors that support or inhibit an individual teacher's instructional decision making. The project explored how Anne's academic preparation, beliefs about reading comprehension instruction, and attitudes toward teacher-student interaction influenced her efforts to employ comprehension strategy instruction. The results of the study suggest that three factors were pivotal in Anne's successful implementation of reading strategy instruction: pedagogical beliefs, classroom relationships, and professional community. Research on instructional change generally focuses on issues of time, resources, feedback, and follow-through. The research reported here recognizes the importance of these components, but expands contemporary thinking by showing how, in Anne's case, a teacher's existing theories, her relationship with her students, and her professional interaction with peers impact instructional decisions.