The Coordination Chemistry of the Hydrous Oxide--Water Interface. Surface Charge and the Electric Double Layer. Adsorption. The Kinetics of Surface Controlled Dissolution of Oxide Minerals: An Introduction to Weathering. Precipitation and Nucleation. Particle--Particle Interaction. Carbonates and Their Reactivities. Redox Processes Mediated by Surfaces. Heterogeneous Photochemistry. Regulation of Trace Elements by the Solid--Water Interface in Surface Waters. References. Index.