Self-efficacy is frequently explored as a construct within assessments in counselor education (Crutchfield & Borders, 1997; Cashwell & Dooley, 2001; Kozina et al., 2010). However, despite the importance of advocacy in our field, there is a lack of research that measures self-efficacy in relation to advocacy attitudes and behaviors (Smith et al., 2009). Specifically, there is an absence of literature exploring the macrolevel of advocacy: public policy engagement. This study developed and validated the initial version of the Self-Efficacy and Public Policy Engagement Inventory (SEPPEI), an assessment that explores self-efficacy and public policy engagement of masters counseling students enrolled in the Council for Accreditation of Counseling and Related Educational Programs (CACREP) accredited programs in the United States. A quantitative, cross-sectional design utilizing a web-based, anonymous survey composed of 30 items (11 demographic items, 19 SEPPEI items) was successfully completed by 137 participants. Upon analyzing the data via Exploratory Factor Analysis (EFA), results indicated that 7 items composing a two-factor structure ("Global Understanding" and "Tangible Action") emerged. These factors support the hypothesis that the SEPPEI measures self-efficacy and public policy engagement with reliability and construct validity. Furthermore, future research to expand upon the validity of the SEPPEI to support advocacy in counselor education and the counseling profession is explored. [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.]