The Internally Assure the Quality of Assessment chapter provides learners with the knowledge and practical skills required to maintain consistency, fairness, and reliability in assessment decisions across a range of vocational and professional learning environments. It explores the purpose and principles of internal quality assurance (IQA), highlighting how effective quality assurance systems support valid assessment practices, regulatory compliance, and continuous improvement. Learners will develop an understanding of the responsibilities of internal quality assurers and their role in safeguarding assessment standards while promoting confidence in qualifications and learner achievement. Throughout this chapter, learners will examine key quality assurance activities, including planning and conducting sampling, monitoring assessment practice, reviewing assessment decisions, providing constructive feedback to assessors, and maintaining accurate quality assurance records. The chapter also considers the importance of standardisation, risk-based sampling, evidence evaluation, professional communication, and ethical decision-making. Learners will explore how internal quality assurance contributes to organisational quality systems, supports assessor development, and ensures that assessment practices remain valid, reliable, fair, sufficient, authentic, and compliant with awarding organisation and regulatory requirements. By the end of this chapter, learners will be able to apply recognised internal quality assurance principles to real assessment settings, evaluate assessment practice against established quality standards, and implement effective quality improvement strategies. They will gain the confidence to monitor assessment processes, support assessors through professional guidance, identify areas for improvement, and contribute to maintaining high standards of assessment quality. These competencies prepare learners to perform the internal quality assurance role effectively while promoting continuous improvement, learner confidence, and the integrity of assessment within education, training, and workplace environments.