On October 27, 2022, the inspirational and highly influential hydrologist Ignacio Rodríguez-Iturbe suddenly passed away. He was Distinguished University Professor and Wofford Cain I Chair Professor Emeritus at Texas A&M University, and James S. McDonnell Distinguished University Professor Emeritus of Civil and Environmental Engineering, Princeton University. Ignacio, a master of contemporary thought and a pathbreaking scientist, was at the center of the cultural process that transformed the field of hydrology from an empirical branch of applied engineering to a mainstream environmental science. He showed creatively and rigorously that the analysis, synthesis, and sampling of hydrological processes could pave the way for a new and deeper understanding of floods, droughts, and a "fair" distribution of water, including water controls on living communities—in a nutshell, how nature works through the inner workings of the water cycle. Rodríguez-Iturbe’s pioneering work has influenced generations of researchers across many fields and around the world and left a long-lasting legacy through many disciples and in a large number of young people, students of all types, whose lives he changed for the good by his intellectual mark and empathic maieutics. Ignacio made each student and collaborator alike feel special wherever he went, and mobilized entire communities to shift their foci to modern hydrologic research. Within hydrology, his work was wide-ranging and highly mathematical, blending theory from spatial point processes and fractal mathematics to the dynamics of river basins and other hydrological patterns. However, his contributions went well beyond hydrology to include ecophysiology and plant community ecology, and his efforts basically created a new discipline at the interface between ecology and hydrology. According to Google Scholar, he has an h-index above 100, and he remained active until his death.