This volume considers fairness in high-stakes international assessments that gauge differences in educational strengths and ranking of countries around the world and improve teaching and learning. It explains the current state of international assessments and how countries have used results from assessment initiatives to inform educational policy and practice at the national level; various international assessment programs, focusing on the mathematics part of the Trends in International Mathematics and Science Study assessment and addressing the creation of the Standards for Educational and Psychological Testing; the author’s model, The Arbuthnot Assessment Fairness Framework, to examine test and item-level performance patterns and fairness issues; how to use it and its four phases to inform stakeholder groups about test fairness issues and differences in performance patterns, using the examples of Chinese Taipei, Finland, the US, and Qatar in terms of the Trends in International Mathematics and Science Study assessment, with details on their cultural impact, performance patterns, and educational reform policies; and how to analyze data and use multiple data sources to examine issues of fairness on international assessments.