Sonochemistry is a rapidly growing field of research and industrial application. Sonochemistry refers to the effects of sound and ultrasound on chemical reactions. Chemical activation and process intensification is provided through ultrasonically-induced cavitation in a liquid medium. The present review describes some fundamentals of cavitation related to sonochemistry, sonochemical equipment, especially sonoreactors, and the present status of sonochemical reactor design. Some problems that should be investigated in more detail are listed.