Preface -- Contents -- Summary -- 1 Introduction -- 2 Sensing from the Molecular to the Global Scale: New Opportunities and Challenges -- 3 Integrating Observations, Models, and Users -- 4 Case Studies on Integrated Observatories for Hydrological and Related Sciences -- 5 Synthesis, Challenges, and Recommendations -- References -- Appendix A Key Water Science Research Questions and Challenges -- Appendix B Planning, Designing, Operating, and Utilizing the Results from an Integrated Observational-Modeling System -- Appendix C A Complementary National Research Council Study on Earth Science and Applications from Space -- Appendix D Biographical Sketches Committee on Integrated Observations for Hydrologic and Related Sciences.