Developed by the United Nations Economic and Social Commission for Western Asia (ESCWA) and the United Nations Children's Fund (UNICEF), the report entitled Social spending, expenditure efficiency and fiscal sustainability in the Arab States presents a comprehensive assessment of how public resources are invested in people. It introduces a whole-of-budget approach through the Social Expenditure Monitor (SEM), highlighting efficiency and equity gaps across seven dimensions of social spending. The report defines an efficiency frontier to benchmark the effectiveness of resource use in achieving human development. It also demonstrates how countries can achieve improved outcomes through more strategic and effective spending. Aligned with the Sevilla Commitment on Financing for Development, the report outlines actionable pathways to strengthen fiscal systems using data-driven and AI-enabled tools that assess fiscal space, enhance efficiency and improve budget effectiveness, in line with national priorities for inclusive and sustainable development.