The current global pandemic of Covid-19 is a health and broader crisis of overwhelming proportions, threatening livelihoods, economies, and societies, particularly those already experiencing the greatest vulnerabilities. In putting the lives of millions of people at risk, creating uncertainties, heightening existing fragilities, and exacerbating inequalities, it has become a truly global challenge. Crisis also brings opportunity, however, and in addition to short- and mid-term responses, this is a time to explore and work towards a genuine transformation of ideas, policies, programmes, and practices. This may all be encapsulated in the overall notion of building back a better world. Against this backdrop, this article introduces this IDS Bulletin issue which asks, fundamentally, how we can collectively and equitably shape and even transform our shared future, in the light of experience of Covid-19, and what steps are necessary for us to do so. It draws upon strategic approaches guiding the efforts of two highly engaged organisations: Irish Aid, Ireland; and the Institute of Development Studies, UK. This editorial introduction explores lessons learned from the impact of Covid-19 by highlighting some key viewpoints and evidence provided in the articles3 that follow. It then offers a number of priority areas for action looking forward, as well as several principles that may help to guide those future actions in efforts to build back a better world.