Bill is the President and CEO of Stone Aerospace, and Founder and Chairman of Shackleton Energy Company (SEC). He worked as an engineer at the National Institute of Standards and Technology (NIST) from 1980-2004, and established several companies, including Cis-Lunar Development Laboratories. Bill's current focus is on the development of autonomous underwater vehicles (including DEPTHX, ENDURANCE, and VALKYRIE) for exploration of under-ice water bodies in Antarctica, and to serve as functional prototype systems for future unmanned exploration of sub-surface oceans of Jupiter’s moon Europa, in search for microbial life. Through SEC, Bill is developing a business plan to mine water from the poles of the Moon, as a source of oxygen, water, and rocket fuel to support manned and unmanned vehicles in low earth orbit. He has spent the past three decades developing some of the world’s most sophisticated underwater life-support systems, including mixed-gas closed-circuit rebreathers – initially through Cis-Lunar Development Laboratories, and currently in collaboration with Poseidon Diving Systems in Sweden. In addition to his work as an engineer, inventor, and entrepreneur, he is also an expeditionary cave explorer, having led or participated in over 40 international expeditions. He currently serves on the Board of Directors as President of the 501(c)3 non-profit United States Deep Caving Team. He has written more than 140 articles on subjects ranging from structural and civil engineering, to life-support systems and autonomous vehicle design, to exploration activities in the world’s deepest caves (including the book, Beyond the Deep: The Deadly Descent Into the World's Most Treacherous Cave). The work from these different enterprises has been featured in many scientific and major media articles (e.g., National Geographic, Wired, Popular Science, IEEE Spectrum, The Explorers Club Journal) as well as books (e.g., Blind Descent: The Quest to Discover the Deepest Place on Earth). Bill's work has also been featured in many film projects and shared through numerous public presentations (including a TED talk).