This work explores the historical, conceptual, theoretical and practical dimensions of school-based assessment (SBA) in a public examination. In part 1, Griffith offers the history and context for the exploration of the issues of SBA in a public examination and reviews the history and concept of public examinations and the evolution and mandate of the Caribbean Examinations Council as a public examinations board serving member countries of the region. In part 2, he provides the foundations for a discourse of the concept, theory and practice of SBA in the context of the public examinations of the Caribbean Examinations Council and explores key issues in SBA in a public examination. In part 3, he examines a number of new directions and practices related to SBA in a public examination, for example, the use of an alternative (external) paper to assess the same competencies developed and assessed in the SBA undertaken in schools, the implementation and assessment of group work in SBA, the use of a single project for the SBA of a cluster of subjects, and ways in which the benefits of SBA in a public examination may guide practice at all levels of the education system to improve student learning and assessment.