Optimism is arguably our most underappreciated resource in a time of crisis. While it’s natural, and emotionally necessary, to confront the reality we face, the only thing that will stop us from succumbing to a doomful and disempowered mindset is the belief — and the reasons to believe — that we have a fighting chance. We have the resources, the research, the technologies, the deployment channels and the skills to act on climate successfully; we just need the collective will and belief to coordinate all these efforts. How do we unleash this power? How can we turn optimism into a global strategy?