High-stakes testing across Europe’s diverse linguistic and cultural populations presents a key challenge: ensuring results reflect true competence rather than barriers related to language, culture, and psychological readiness. This session introduces an integrated framework for reducing the Construct–Access Gap—the difference between true capability and demonstrated performance—by combining culturally sensitive test adaptation with test readiness science grounded in performance psychology. Europe’s complexity, including multiple languages, cultural variation, and rising expectations for fairness, requires a shift in how testing is designed and experienced. The Construct–Access Gap reframes validity as: Test Performance = Competence × Access × Readiness. Closing this gap requires culturally aligned assessment design and readiness interventions that strengthen motivation, confidence, and resilience, improving fairness, validity, and performance.