This book addresses the topic of soil’s physical properties and processes with particular reference to agricultural, hydrological, and environmental applications. The book is written to enable undergraduate and graduatestudents to understand soil’s physical, mechanical, and hydrological properties, and develop theoretical and practical skills to address issues related to sustainable management of soil and water resources. Sustainable use of soil and water resources cannot be achieved unless soil’s physical conditions or quality is maintained at a satisfactory level.Fertilizer alone or in conjunction with improved crop varieties and measures to control pests and diseases will not preserve productivity if soil’s physical conditions are not above the threshold level, or if significant deterioration of physical conditions occur. Yet, assessment of physical properties and processes of soil is not as commonly done as that of chemical or nutritional properties, and their importance receives insufficient attention. Even when information on soil’s physical properties is collected, it is not done in sufficient detail and rarely beyond the routine measurement of soil texture and bulk density.