This book, which is divided into three parts, gives a state-of-the-art report on technical developments in instrumentation and on theoretical advancements in acoustic remote sensing. It explains the utilization of acoustic techniques in studies related to the structure of the lower atmosphere and oceans and discusses various atmospheric and oceanic applications. The potential and limitations of acoustic remote sensing are also described. This book will be useful to researchers, graduate students, and teachers interested in the structure of the atmosphere and oceans.