The world is at a crucial juncture where decisive action is urgently needed to tackle climate change. However, without consideration for distributional concerns, the costs associated with climate mitigation policies risk falling disproportionately on certain workers, sectors, and socioeconomic groups, exacerbating existing inequalities and undermining popular support for climate action. Embedding the principle of a just transition into climate strategies is crucial to address these issues and accelerate climate action. Drawing on recent OECD work, this paper examines the development of, and different approaches to, the concept of just transition, including how it is put into practice by public and private actors. It addresses the impacts of the net-zero transition on labour markets and households, as well as specific issues faced by developing countries, and outlines key policy tools and approaches available to governments.