The No Child Left Behind (NCLB) Act of 2001 requires all schools to be accountable for student performance. High-stakes accountability represents a growing concern among the field of education. Literature supports that teachers are vital to the success of students; however, the impact of high-stakes testing on instructional practice is changing the way teachers' approach teaching and learning. In an effort to identify the instructional practices being used to support high-stakes accountability mandates, a qualitative study was conducted to identify the perceptions of teachers and administrators of the impact high-stakes testing has on instructional practices. Ten third through fifth grade teachers and administrators in north central Wyoming were selected as participants of the study. At the completion of the in-depth interviewing process, qualitative data was analyzed into major themes using the participants' in-depth interview responses. Three major themes emerged as a result of the data analysis: Systems, Implementation, and Professional Response. More specifically, the study discusses how the accountability system impacts instructional practice and curriculum implementation and professional responses to the accountability mandate set by legislators. Analysis of the data revealed teachers and administrators spend time preparing for high-stakes tests; however, students' well-being and intellectual growth were more of a priority. Teachers and administrators claimed they were not willing to compromise students' learning for an assessment that is unreliable and an invalid measure of what students' actually know. In this study, it was concluded that the general consensus to the perceptions of teachers and administrators of the impact high-stakes testing has on instructional practices is minimal. Although teachers and administrators shared concerns about the accountability system, its implementation, and their professional realities, teachers and administrators spoke more about employing best instructional practices to ensure students will be successful citizens. Lastly, this study concludes with future research recommendations, which will be of interest to other researchers and educators. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]