This single-case research design study examined the degree of change in school-counselors-in-training self-report of self-efficacy in response to a narrative-based supervision intervention using the Counselor Self-Efficacy Scale. The narrative-based supervision intervention consisted of ten prompting questions, five questions focused on the school counselor and student relationship, while the remaining five questions focused on the supervisor and supervisee relationship. Participants received the narrative-based supervision intervention across three consecutive weekly sessions each. Participants were four school counseling internship students. Results showed that participants who showed decreasing trend scores before the intervention, showed an increase in self-efficacy score at the onset of the intervention and increasing trend scores in self-efficacy throughout the intervention phase. Participants who showed increasing trend scores before intervention, showed an initial decrease in scores in self-efficacy with slight increasing trends during the intervention phase. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]