Increasing teacher efficacy poses challenges to educational leaders, highlighting the need for a study of the awareness and development of strengths related to teacher efficacy. The purpose of the current study was to examine the effect of the awareness and development of strengths on teachers' perceived self-efficacy, as well as to determine if treatment type or years of experience were differentiating factors in the level of self-efficacy change. Teachers (N = 45) from a suburban district participated in a two-tiered experimental research design. Participants completed a pre-/post-Teachers' Sense of Efficacy Scale (TSES) and were randomly assigned to Treatment Group (TG) 1, TG2, or the Control Group (CG). TG1 became aware of their strengths using the Clifton StrengthsFinder (CSF) and completed two strengths validation activities independently. TG2 completed TG1's activities and five strengths development activities at two training sessions. CG received no intervention. A one-way ANOVA examined changes in teachers' level of self-efficacy following participation in TG1 or TG2. Results suggest there is not a significant effect of the grouping variable based on an alpha of 0.05; however, the relatively large gains in self-efficacy scores in the two treatment groups as compared to the CG suggest that both exposure to and instruction in signature strengths appear to be related to changes in levels of self-efficacy. A multiple regression was conducted predicting the self-efficacy changes related to treatment group variable and years of teaching experience. Overall, the regression was not statistically significant; however, the treatment type predictor was significant. [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.]