Cobalt (Co) is an essential metal for the development of energy-transition technologies, decarbonising transportation, achieving several sustainable development goals, and facilitating a future net zero transition. However, the supply of Co is prone to severe fluctuation, disruption, and price instabilities. This review aims to identify the future evolution of Co supply through technologically resilient and environmentally sustainable pathways. The work shows that advances in both primary and secondary sources, Co mining methods and recycling systems are yet to be fully optimised. Moreover, responsible sourcing from both large mines and small artisanal mines will be necessary for a resilient Co supply. Regulatory approaches may increase transparency, support local mining communities, and improve secondary Co recovery. Novel Co supply options, such as deep-sea mining and bio-mining of tailings, are associated with major techno-economic and environmental issues. However, a circular economy, keeping Co in the economic loop for as long as possible, is yet to be optimised at both regional and global scales. To achieve environmental sustainability of Co, economic incentives, regulatory push, and improved public perception are required to drive product innovation and design for circularity. Although the complexity of Co recycling, due to lack of standardisation of design and chemistry in batteries, is an impediment, a sustainable net zero transition using Co will only be possible if a reliable primary supply and a circular secondary supply are establishe
