Beyond rigorous reading instruction in America's high schools, writing instruction in the 21st century must be addressed if students will be equipped with the critical thinking skills they need to be successful. Teachers, however, need training in implementing innovative methods in writing instruction to effect change in student achievement. This quantitative, quasi-experimental study attempted to determine what effect professional development through in-person training and follow-up support through coaching emails have on teachers' perceived self-efficacy in implementing mentor text instruction for writing. Data were collected from 9 teachers who attended a 2-hour professional development session on strategies for using mentor texts. Before and after the training, teachers responded to the Teacher Self-Efficacy Scale (TSES). Participants received 5 weeks of follow-up support through coaching emails, which included classroom exemplar videos, articles on mentor text instruction, and lesson plans for using mentor texts. A 1-sample Wilcoxon Signed Rank Test was used to compare participants' median scores on the TSES before and after the in-person training and then to compare the participants' median scores on the TSES before and after receiving follow-up support through coaching emails. Further research may demonstrate more variations of professional development and follow-up support as well as the specific uses and benefits of mentor texts in writing instruction for various grade levels and for various writing tasks as well as how it affects students' reading ability. [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.]