Front Matter -- Acknowledgments -- Contents -- Overview -- 1 Wolman Lecture: Hydrologic Science . . . in Landscapes . . . on a Planet . . . in the Future -- 2 Aquatic Ecosystems: Defined by Hydrology. Holistic Approaches Required for Understanding, Utilizing, and Protecting Freshwater Resources -- 3 Hydrologic Measurements and Observations: An Assessment of Needs -- 4 Ground Water Dating and Isotope Chemistry -- 5 Streamflow Prediction: Capabilities, Opportunities, and Challenges -- Appendix Biographical Sketches of Abel Wolman Distinguished Lecturer and Symposium on Hydrologic Sciences.