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In this 50th Anniversary Collection, Ambio presents and discusses articles that importantly contributed to understanding the historical causes and development of the Anthropocene (Folke et al. 2002; Liu et al. 2007; Steffen et al. 2007, 2011). The Anthropocene denotes the current geological age, viewed as a period during which human activity started to fundamentally alter the synergetic dynamics of climatological, geological and biological processes on Earth (Pálsson 2020, p. 10). Parallel to any indicator that measures the impact of human life on Earth (see Steffen et al. 2007, p. 617), the prevalence of the term Anthropocene in the human written record grows ferociously (Fig. 1). Except the popularity of the term lags 60 odd years behind the reality it describes. As if the epistemology of the Anthropocene is trying to catch up with its ontology. The authors of the four Ambio articles that feature in this anniversary collection have written personal reflections about the origins of their work and its impact on science and society (Folke et al. 2021; Liu et al. 2021; Steffen 2021). Included as well are the contributions of two academic peers who place these articles in the growing, heated, and interdisciplinary debate about the Anthropocene as reality and idea (Castree 2021; O’Brien 2021). Reading the four articles again, I found it striking how they together exemplify a leading scientific perspective on the history of global social-ecological interactions. Central to this perspective is the conviction that human societies are interdependent with natural environments as ‘‘systems’’ (Folke et al. 2002, p. 437); an expansion of this socialecological interdependency to encompass the whole planet, or—to keep with the discourse—‘‘Earth system’’ (Liu et al. 2007, p. 645); and an appeal to humanity to take responsibility for this system through ‘‘planetary’’ or ‘‘earth stewardship’’ (Steffen et al. 2011, p. 749–757). The peer reflections discuss why and how this perspective has progressed our understanding of the history of socialecological interactions, but also why their framing of the impact of human society on Earth triggered debate (Castree 2021; O’Brien 2021). This debate concerns, amongst other things, the appeal to humanity at large (cf. the calls for Earth stewardship) to redress their impact on nature. The peer reflections also notice that a gap persists to this day between knowing and causing the Anthropocene—the evidence for the risks that come from the expansion of human society on planet Earth is abundant, but people and societies fail to take precautionary actions based on this knowledge. One of the authors of the four articles, Will Steffen soberly concludes in his personal reflection that the caution his work raised ‘‘has fallen on deaf ears’’, and suggests that we now need solutions ‘‘rather than yet another diagnosis of the problem’’ (Steffen 2021; see also Ripple et al. 2017). Considering the knowledge and debate about the Anthropocene, and the immediate signs of the climate emergency that we are facing what are the solutions? What are the ‘‘deep transformations’’ (O’Brien 2021) that so many scientists, students, and others ask for and how can these be realized? I hope that the articles included in this 50th Anniversary Collection on the Anthropocene might contribute to the solution-oriented science that Steffen advocates. I will conclude this introduction in the same spirit that marks these articles that follow by offering some