The purpose of this study was to identify beliefs about content area literacy commonly held by teachers and to evaluate whether or not these collective professional convictions and suppositions affect disciplinary instructors' implementation of content area reading strategies in their classrooms. A mixed methodology was applied to gather both qualitative and quantitative data from a study sample of 39 middle and high school core and elective disciplinary teachers. A validated assessment scale was administered to identify professional beliefs held by study participants about reading instruction in content area classrooms. Individual interviews were also conducted to examine participants' professional practices related to implementation of reading strategy instruction in content area classrooms. The results of the study found that, in large numbers, secondary teachers do harbor attitudes, in five broad categories, toward content area reading instruction that are unfavorable and that implementation of strategies in their classrooms, lesson plans and curricula are negatively impacted by the paradigms held.