This volume questions the validity issues surrounding educational assessment programs and their appropriate uses in applied contexts. The authors break new ground in terms of validity theory and practice, offering recommendations, frameworks and assessment solutions that are broadly applicable in different regions. Chapters discuss the social consequences of validity oversights in high stakes testing, evaluation and accountability contexts. Questions addressed include: Do validity issues arise due to the technical complexities in assessment programs today, or a lack of awareness and inattention to technical limitations of assessment instruments by users? Is there a communication divide between educational policy-makers and measurement professionals that is obstructing more valid use of educational assessments and other forms of data? The prominent authors, representing voices of educational policy-makers, leaders, and recognized experts in educational measurement and evaluation from around the world, describe assessment programs in their regions, and appraise the conditions and factors that could enhance valid, equitable or fair assessment practices.