Accountability is a critical part of achieving success in mutual goals and relationships. Throughout Asia and the Pacific, national authorities remain off track in achieving Agenda 2030, particularly Sustainable Development Goal Four (SDG4) on quality education. Persistent challenges, including the lack of data, effective measurement, and accountability mechanisms, continue to impede progress. This paper explores the complexities in a proposed "accountability space," and showcases collaborative governance and accountability in higher education for sustainable development (HESD) in the Asia-Pacific region as a case study. The lead United Nations agency for higher education, UNESCO, monitors SDG4 progress guided by normative instruments such as the Tokyo Convention in Asia and the Pacific and the Global Convention on Higher Education. These conventions establish frameworks for international cooperation through policies and practices that facilitate student and professional mobility. Drawing on policy analysis, implementation reports, and anonymized data from 17 countries in the region, this case study utilises a framework for accountability applied to higher education. Findings suggest how complex accountabilities can be effectively measured using six metrics--transparency, liability, controllability, responsiveness, and responsibility--to enhance the relevance of higher education for sustainable development. The study recommends creating more inclusive collaborative spaces and calls for open accountability in higher education.