The peculiar characteristics of clays provide it with very interesting adsorption qualities, especially for polar or ionizable molecules. Some of these characteristics include the silicates’ sheet structure that makes a large surface area accessible for adsorption; the usually significant surface charge that can be responsible for strong electrostatic interactions; and clays’ swelling properties and presence of exchangeable surface cations that facilitate ion-exchange mechanisms. Added to their wide availability and associated low cost, these characteristics have motivated in recent years an increasing interest in utilizing natural, processed or chemically-modified clays for the removal of organic contaminants from aqueous solutions. This book discusses the application of clay materials for the removal of organic compounds from contaminated waters. It also discusses several other topics that include time and temperature related behavior of clays; mechanical treatment of clay minerals; the workability of natural clays and clays in the ceramics industry; recent advances in hydraulic performance of clay liners; and the genesis, properties and industrial applications of bauxitic lithomargic clay.