Water in the soil is absorbed, utilized, and transpired by the plants growing on it. Further, as already noted, it affects the properties of the soil and the reactions and processes that occur therein. Plants are sensitive to these properties, reactions, and processes. Hence, soil water affects plant growth and development both directly and indirectly. In view of the importance of soil-water interrelations and their quantitative description, a symposium was held in 1971 at the annual meetings of the Soil Science Society of America on the topic "Field Soil Water Regime." This volume includes the papers presented at that symposium. Although it is recognized that these papers do not include all aspects of the subject, it is hoped that they will facilitate understanding and illustrate the wide range of activities related thereto.