A persistent challenge facing education policies has been the difficulty of ensuring local implementation of instructional reforms by teachers. Despite numerous instructional reform initiatives, teacher practices have remained relatively constant over the past century. Some research studies attribute the lack of implementation of local reforms to teachers’ interpretation of the policy messages underlying these reforms, which may be influenced by their views of their discipline and their students, and by the social context of the school, which influences not only their interpretation, but also the extent and quality of implementation. In this study, the authors examine teachers’ response to policy messages related to mathematics and science reforms. Using information collected from semi-structured interviews, teacher surveys, and teacher daily logs, the authors identify the policy messages that influence teachers and discuss the factors that either facilitate or hinder teachers’ implementation of these policies.