This policy brief has been prepared by the Australian Council for Educational Research (ACER) for the UNESCO International Institute for Educational Planning (IIEP) Regional Conference, held in Manila from 5 to 7 November 2024. This brief is in response to the conference sub-theme of, 'Learning, equity and well-being: foundational literacy, numeracy and the use of learning assessment data.' This sits under the overarching conference theme, 'Educational planning in Asia: Common vision and future prospects.' The remainder of this paper is divided into 3 sections. It begins by outlining ACER's definition of a learning assessment, followed by an overview of the potential that a robust learning assessment can provide to policy and planning arms of government. Next, 2 case studies are presented on previous and ongoing research undertaken by ACER, in collaboration with governments and education stakeholders, on how learning assessments have been used to further understand foundational literacy and numeracy. The paper ends with practical and actionable recommendations that speak to the conference theme, 'Educational planning in Asia: Common vision and future prospects.' [This paper was prepared for the Asian Network of Training and Research Institutions in Educational Planning conference, which is supported by the UNESCO International Institute for Educational Planning.]