The overarching goal of this dissertation is to examine institutional change initiatives in STEM and to understand the impact of engaging with a specific change strategy on a biochemistry educator's instructional practice. Institutional change initiatives involve executing an intentional strategy to influence teaching practices within a specific institution. This research investigates NSF-funded change initiatives at three public research universities that were focused on encouraging the adoption of evidenced-based instructional practices (EBIPs) by STEM faculty. As part of an effort to understand how the three institutions approached this task, framework analysis was performed using the initiative's annual reports to NSF. Further examination of the interaction between Community of Practice (CoP), a type of enacted change strategy, and how its impact's an instructor's use of EBIPs related to assessment. Instructors make assessment decisions based on their knowledge and experiences. Assessment practice is an essential element of instruction, and the outcomes of assessments have a broad impact on both students and instructors. Efforts to provide strengths-focused, relevant professional development support regarding assessment are enhanced by greater understanding of the complex nature of assessment practices. In this study, the Teacher Assessment Literacy in Practice (TALiP) framework was used along with framework analysis methodologies to guide our investigation of one biochemistry instructor's assessment literacy, relevant to her integration of a biochemistry threshold concept, the physical basis of interactions (PBI), into her course. Analysis revealed that community support and self-reflection influenced the instructor's enactment of specific assessments aligned with her instructional goals. [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.]