The rise and fall of civilizations have been closely linked withthe use and abuse of soil and water resources. There is little reasonto believe that these linkages will disappear in the future. Peopleneed soils, and soils need people. Soil classification is a technique to systematically organize data,information, knowledge and speculation about soils. In the naturalworld, soils are understood as the products of soil forming processesthat are influenced throughout time by the soil forming factors ofparent material, biota, climate, and topography. In the world ofhuman-induced changes of factors and processes, soils are under-stood as complex entities whose multiple functions are essential for asustainable global habitat that provides a reasonable quality of life forall things.