Cave diving has been called the most dangerous participatory sport in the world. It doesn't have to be. With proper training, experience, and guidance, you can be a skilled cave diver and enjoy this challenging and rewarding activity for a lifetime. With decades of technical diving instructor experience, including world record cave dives, and paradigm-changing underwater exploration, Scuba Diving Hall of Fame Inductee and Canadian Explorer-in-Residence Jill Heinerth has created this contemporary cave diving instructional guidebook. Generously illustrated, "The Essentials of Cave Diving - 4th Edition" contains practical, 21st century underwater knowledge, including sidemount techniques and the latest in rebreather technology. Encompassing all levels of cave diving, from entry-level to expert, this manual is an essential tool; appropriate and relevant to all cave training disciplines.