1. THE REACTIVE SOLID SURFACES IN SOILS -- 1.1 Structural chemistry of the surface-reactive solid phases in soils -- 1.2 Surface functional groups in soil clays -- 1.3 Solid surfaces in natural soils -- 1.4 Specific surface area -- 1.5 Surface charge density -- 2. THE STRUCTURE OF WATER NEAR CLAY MINERAL SURFACES -- 2.1 Liquid water -- 2.2 Electrolyte solutions -- 2.3 Water near phyllosilicate surfaces -- 2.4 The solvent properties of adsorbed water -- 3. THE ELECTRIFIED INTERFACE IN SOILS -- 3.1 The balance of surface charge -- 3.2 Points of zero charge -- 3.3 Potentials near an electrified interface -- 3.4 Electrokinetic phenomena -- 3.5 Negative adsorption -- 4. INORGANIC AND ORGANIC SOLUTE ADSORPTION IN SOILS -- 4.1 The adsorption isotherm -- 4.2 Adsorption versus precipitation -- 4.3 Metal cation adsorption -- 4.4 Inorganic oxyanion adsorption -- 4.5 Organic matter adsorption -- 5. CHEMICAL MODELS OF SURFACE COMPLEXATION -- 5.1 The diffuse double layer model -- 5.2 Surface complexation models: statistical mechanics -- 5.3 The constant capacitance model -- 5.4 The triple layer model -- 5.5 The objective model -- 5.6 The structure of surface complexation models -- 6. SURFACE CHEMICAL ASPECTS OF SOIL COLLOIDAL STABILITY -- 6.1 The Smectite Quasicrystal -- 6.2 Interparticle forces in phyllosilicate suspensions -- 6.3 The stability of soil colloidal suspensions.