Given that we spend about one third of our lives asleep (if we're lucky), it's natural to wonder why we sleep - indeed, why every animal sleeps. It's also natural to wonder what happens when you don't get enough sleep. Well, you need look no further for compelling answers to these fundamental questions. Simply put, this is a tour de force of the world of sleep: accessible to a broad audience, beautifully written, and absolutely fascinating. The author has a way of making the science come to life with thought-provoking stories and analogies. He has so thoroughly convinced me of the importance of a good night's sleep that the only reason I put the book down at night is to make sure I get one. I recommend watching an interview or talk by Matthew Walker for inspiration, and then diving into his book.