Book excerpt: Published by the American Geophysical Union as part of the Special Publications Series. In the early 1980s, the Department of Hydrology and Water Resources at the University of Arizona started a tradition: an annual public lecture to perpetuate the memory of one of its most original thinkers who passed away at an early age, Chester C. Kisiel. At that time, the department was quite young—a little over ten years old—and so was the University of Arizona, not quite a century old. The overall atmosphere was extremely stimulating, faculty members and students were curious and excited, wishing to learn and understand more about the natural phenomena that transform precipitation into water and the possible development of regional waters for human uses. The preparation and delivery of these lectures were entrusted by the department to outstanding scientists in the fields of hydrology and water resources, thus attaining a double objective. On the one hand, the lectures became salient points on a time trajectory when specific facets of the broad agenda of scientific issues studied in the department were brought to the limelight of a public discourse. On the other hand, the lectures also provided opportunities for reflection on contemporary problems and on the approaches for their study and analysis.