The study of the effects of ultrasound waves on a chemical reaction is known as sonochemistry. Ultrasound radiation (between 20 kHz and 2 MHz) is used to drive chemical and physical processes in solution. When ultrasound waves pass through liquid, they generate tiny bubbles that expand and then collapse quickly. This process releases energy, which can speed up the chemical reactions. Sonochemistry is considered a sustainable technology because it often utilizes less energy, requires fewer toxic chemicals, and generates less waste compared to traditional chemical processes. Ultrasound waves are utilized in various processes including synthesis, crystallization, and purifications and find applications in various sectors like pharmaceuticals, material sciences, agriculture, food processing, and environment science. This book is focused on applications of sonochemistry. It begins by explaining the basics of the technology and moves on to describing applications in the fields of chemistry, chemical engineering, and environmental engineering, and discussed applications currently being developed and future outlook.