I had the immense pleasure and privilege of working with Will Steffen when I was a PhD student and postdoctoral fellow in the Centre for Resource and Environmental Studies then Fenner School of Environment and Sustainability at the Australian National University, 2004-2010. He was a rock star in the world of climate science even then, innovating on the Anthropocene and planetary boundaries, but always had time to talk and laugh as well as to mentor and lead. So sad to hear that pancreatic cancer took him this week. A massive loss to the people and the planet. Vale, Will.