This chapter presents the management of rangeland soil and water as a practical subject with emphasis on erosion and its control, and development of water for use, loosely called “water harvesting.” Soil erosion relates to the movement and resistance of soil to the forces of water and wind. Splash erosion destroys soil structure, places particles in suspension, and mixes water and soil. Wind erosion occurs where the soil is exposed to the dislodging force of moving air and varies with structure of dry soil; surface roughness; slope; cover on the soil; and velocity, angle of incidence, and duration of air movement. Seeded contour furrows made with a lister with native shortgrass strips between proved to be the best rehabilitation method on sandy soils in eastern Montana. Water harvesting means collection from large or small areas and storage in the soil profile for plant use or in tanks of various kinds for irrigation, animal, and human use.