Cédric Verdier’s *Plongée profonde et plongée technique* offers a thorough introduction to the world of deep‑sea and technical diving. Drawing on the author’s extensive experience, the work explains the physiological challenges of extended bottom time, the equipment configurations required for mixed‑gas and rebreather systems, and the safety protocols that underpin successful dives beyond recreational limits. Readers will find clear diagrams of dive‑computer interfaces, step‑by‑step procedures for planning decompression stops, and practical advice on handling emergencies in hostile underwater environments. Whether you are a certified diver looking to expand your skill set or an enthusiast curious about the science behind deep diving, the book balances technical detail with accessible language, making complex concepts understandable without sacrificing rigor.