Examination regimes at the end of secondary school vary greatly intra- and cross-nationally, and in recent years have undergone important reforms often geared towards increasing student achievement. This research presents a comparative analysis of the relationship between examination regimes and student achievement in the OECD. Using a micro dataset based on individual records of secondary school students tested as part of the Third International Mathematics and Science Study--and relying on a thorough qualitative review of testing regimes as well as descriptive analyses of OECD, UNESCO, World Bank and PISA data--this study explores the relationship between high school exit exams (particularly external and high stakes) and student achievement. The analysis also explores whether exit exams have a heterogeneous association with student learning, varying by student performance or program of studies, as this might signal that inequalities in student learning may be generated, or maintained, by examination regimes. Results of multivariate linear models (weighted ordinary least squares and quantile regressions) indicate that external exit exams have a small positive association with student achievement. Exams that are high stakes are negatively associated with student achievement, unless those exams are external. Against expectations, the results indicate that the influence of exams is not greater among higher achieving students. On the contrary, limited evidence suggests that exams might have a positive effect among lower achievers. Also contrary to expectations, external exit exams are associated with lower rather than higher variance in student achievement. The study concludes with a discussion of the implications of these results--particularly in the context of prior research. [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.]