Phase-out has emerged as a policy approach to confront multiple sustainability crises. From ozone-depleting substances and hazardous chemicals to fossil fuels and transport technologies, phase-out experiences have been documented by diverse scientific communities. To consolidate this dispersed knowledge and inspire more systematic research, we map the evolution of scientific discussions about phase-out through a systematic literature review. Examining 870 papers published since 1970, we trace the evolving nature of phase-out strategies in terms of targets, geographic and industrial contexts, policy instruments and drivers. This provides a multi-faceted overview of an emerging and rapidly growing ‘phase-out science’ rooted across the full spectrum of scientific enquiry. Evolution of this science is marked by broadening engagement with a growing diversity of targets, contexts, and policies. Our analysis also shows how phase-out policies have recently gained momentum as a tool to tackle climate change, with a particular focus on fossil fuels and associated technologies.