The current study explored the relationship between test-based accountability and teachers' involvement in school-level decision-making and classroom autonomy, examining how this varied by country, specifically in the United States, Australia, South Korea, and Japan. Additionally, the study investigated whether this relationship differs based on principals' level of involvement in school-level decision-making. To this end, I used the 2018 Teaching and Learning International Survey (TALIS 2018) data administered by the Organization for Economic Cooperation and Development (OECD). Over the past two to three decades, there has been a surge of interest in test-based accountability policies across various countries as a way to improve the quality of education and raise student achievement. This interest, in particular, has intensified since the implementation of the No Child Left Behind and international student testing programs, such as the Programme for International Student Assessment (PISA) (Hooge et al., 2012; H.-D. Meyer, 2014; Ozga, 2013). Concurrently, there has been a call for advocating granting teachers greater decision-making authority at the school and classroom levels as a strategy to enhance student achievement, teacher satisfaction, and motivation to improve teaching quality. Although it has been found that test-based accountability policy reduced teachers' school-level decision-making authority and classroom autonomy while increasing those of government and school principals (Hilferty, 2008; Jeong & Luschei, 2018; Kim, 2018; Mehta, 2013b; Smith & Benavot, 2019), few studies have explored this empirically using international data. To understand this relationship, I employed data from TALIS 2018 to examine how test-based accountability policy was associated with teachers' decision-making authorities and how test-based accountability policy shaped the dynamics of decision-making within school organizations. [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.]