Prepared for a Centre for Educational Research and Innovation (CERI) Strategic Education Governance Learning Seminar, this working paper analyses the functioning of accountability mechanisms in the Flemish school system from a complexity perspective, particularly accountability of equity funding in primary and secondary education. The paper shows that accountability mechanisms are not highly developed, specifically to the Flemish government and to the public. As a result, it proved hard to examine if resources were used effectively and efficiently. The paper argues that a long-term perspective and step-by-step approach is needed to create a culture of evaluation and accountability. It is emphasised that a long-term strategy should start with building horizontal and more specifically professional accountability mechanisms, based on a clear picture of how accountability relates to the overall aims and vision of education. The paper suggests furthermore to strengthen the use of knowledge, both tacit knowledge among others from students, as well as knowledge from research.