The book "Quantitative Information Fusion for Hydrological Sciences" offers a comprehensive insight into advanced methods of computer-assisted hydrology. It addresses the quantitative integration of high-quality hydrological field data with geological, chemical, atmospheric, and biological information. The aim is to better characterize and predict natural systems in the hydrological sciences. The authors, including T.-C. Jim Yeh, present a collection of chapters in this specialized book that focus on the latest developments in information fusion. It is aimed at both established scientists and students, covering important aspects such as data fusion techniques, interactive computing environments, and supporting mathematical and numerical methods. Additionally, practical applications of hydrological information fusion are presented, making the book a valuable resource for anyone dealing with the challenges and opportunities in hydrology.