Adsorption from aqueous solutions is important in many tech­ nological areas, like water purification, mineral beneficiation, soil conservation, detergency, and many areas of biology. Recently, adsorption of radionuclides from aqueous solutions has become the focus of attention in assessing the movement of radionuclides through a geologic medium from underground radioactive waste repositor ies. This volume provides a multidisciplinary overview of current work in the area of adsorption from aqueous solutions, and reviews the progress that has been made in the theoretical models for assessing adsorption. Adsorption of heavy metal ions and the effect of complex formation is treated extensively, as are the effects of surface chemical properties of the adsorbent, solution pH, and thermodynamic parameters important in the adsorption process. Adsorption of pesticides and organic polymeric species on different adsorbents are included and implications of adsorption of ions on dental materials are discussed. Also included are studies of the adsorption of radionuclides by geologic media under environmental conditions. The study of the chemical nature of the adsorbed species at the surface by X-ray photoelectron spectro­ sc.opy which often provides mechanistic information for the adsorption process is included for adsorbed metal ions on clay and mineral surfaces.