The use of entrustable professional activities (EPAs) as a basis for assessment may bridge the gap between the theory of competency-based education and clinical practice (ten Cate, 2006).The purposes of this study are to: 1) develop and gather validity evidence EPAs for clinical anesthesia year 1 (CA-1; post graduate year 2 [PGY2)) residents in Anesthesia Residency Programs in the United States (US); 2) create an EPA-aligned workplace-based assessment tool for junior anesthesia residents in the specialty of anesthesiology; and 3) examine validity evidence of the tool using Messick's unified validity framework (content, internal structure, response process, relations to other variables and consequences) (1995). This dissertation applied a construct validity lens to EPA development providing assurance that the EPAs adopted are appropriate for use in workplace-based assessment and entrustment decision-making. These results indicate two of the studied EPAs demonstrate sufficient reliability for decisions. Key enablers and barriers to engagement with the EPA Web App were explored along with behavior domains for entrustment decisions. Feedback analyses demonstrated that comments were critical and relevant to residents helping build alliance with their supervising faculty. The EPA-based assessment provided faculty a framework for giving feedback; for residents, the EPA-based assessment offered an opportunity for discussion with faculty related to their performance. The process described here can be applied to other graduate medical education programs interested in incorporating EPAs in their curriculum as part of programmatic assessment. This study also underscores focused areas for professional development programs to further develop faculty skills on assessment. Implications for practice, limitations, and future research directions are discussed. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]