The Sustainable Development Goals (SDGs), launched by the United Nations in 2015, established ambitious targets to be achieved by 2030, including in education. SDG 4, which focuses on ensuring "inclusive and equitable quality education and promot[ing] lifelong learning opportunities for all", attracted attention from the adult education sector for the role that adult learning and education (ALE) can play in its realisation, and the potential for the SDGs to boost the visibility and support of ALE. This article reports on a study that explored the role of ALE in lifelong learning in eight case study countries (Australia, Brazil, India, Jordan, Kyrgyzstan, South Africa, Thailand and Ukraine). It explores the literature and examines the supports for and challenges of ALE to better understand its potential in helping to realise SDG 4, using a mega-, macro-, meso- and micro-level theoretical framework. Twenty-seven experts in ALE from across the eight countries were interviewed, and data analysis was undertaken using a grounded theory approach. The findings indicate that while SDG 4 was not a strong driver for ALE activities in these countries, initiatives were focused on the same issues targeted by SDG 4. The analysis also points to the unequal policy support given to formal and non-formal ALE activities, and the critical role that ALE networks and associations can play in addressing some of the most ambitious SDG 4 targets.