The exploration of marine resources at depths below 50 meters has only become possible through the use of mixed gases (artificial breathing gases) and appropriately developed diving techniques. This book provides a systematic overview of the subject. It starts with the fundamentals, presents the rules of gas management, and describes the various diving methods. Safety issues are addressed, as well as decompression sickness and its treatment. A special chapter is dedicated to diving in contaminated waters. With its comprehensive treatment of the topic, the book is not only essential reading for all professional divers but also interesting material for all recreational divers. This third edition has been completely revised.