It is now ten years since the first Handbook on Hyperbaric Medicine was published. During this time there have been many major advances: our understanding of the actions of hyperbaric oxygenation has been elucidated by several studies; clinical practice is becoming more scientific; various consensus-derived organisational and operational recommendations and guidelines are now widely accepted. As for Europe, these positive developments are largely due to the continuous action of the European Committee for Hyperbaric Medicine (ECHM). One of the most successful initiatives was the start of a specific European research action sponsored by the EU Co-operation in Science and Technology (COST) programme. The specific COST Action for hyperbaric medicine, COST B14, has been completed and has provided the impetus for the publication of this new Handbook. This book is a reference document for researchers and clinicians, and is also of excellent use for both teachers and students.