This comprehensive contributed volume presents an account of current research and applications of chemical processes occurring at the interfaces of water with naturally occuring solids. Interactions of solutes with the solid surfaces are looked at from a mechanistic and dynamic point of view rather than a descriptive one. Processes discussed and concepts presented are applicable to all natural waters (oceans and fresh waters as well as soil and sediment water systems) and to the surfaces of natural solids such as minerals, soils, sediments, biota, and humus. Chapters progress from theoretical models and laboratory studies to applications in natural water, soil, and geochemical systems, emphasizing those processes that regulate the distribution and concentration of elements and compounds. Topics covered include adsorption mechanisms in aquatic surface chemistry, the electric double layer at the solid-solution interface, aspects of molecular structure in surface complexes: spectroscopic investigations, interpretation of metal complexation by heterogeneous complexants, the role of colloids in the partitioning of solutes in natural waters, and 'from molecules to planetary environments': understanding global change.