Abstract
The field of critical care nephrology recently lost one of its founders and champions. From his seminal and revolutionary investigations into the pathophysiology of sepsis-induced AKI to his relentless efforts to improve the care of patients with AKI through drugs and devices, Rinaldo Bellomo was a larger-than-life figure in intensive care medicine. He was a visionary leader, mentor and thinker and yes, an unrelenting challenger of conventional wisdom. He will be missed by his many friends and collaborators around the world. We are thankful to have walked alongside him and to have been inspired by his humble enthusiasm, openness, and limitless curiosity.