Changes in the system of vocational education, at least in The Netherlands, are based on the idea that the curriculum should focus more on competencies and work-related experiences. In a competency-based curriculum the content is not the central issue but the assessment and monitoring of what is learned and acquired relevant to (later) successful performance. Therefore, it is essential to link assessment with instruction that is focused on performance and aligned with later work. In this paper a framework is developed showing how to organise curriculum and instruction around competencies in vocational education. As an example, the Educational Assessment and Development system is introduced to highlight procedures and experiences of the integration of assessment with instruction in an institute for vocational education and to draw some lessons from this case for future design and construction of curricula.