The study of sexual physiology - what happens, and why, and how to make it happen better - has been a paying career or a diverting sideline for scientists as far-ranging as Leonardo da Vinci and James Watson. The research has taken place behind the closed doors of laboratories, brothels, MRI centers, pig farms, sex-toy R&D labs, and Alfred Kinsey's attic. Mary Roach, "The funniest science writer in the country" (Burkhard Bilger of The New Yorker), devoted the past two years to stepping behind those doors. Can a person think herself to orgasm? Can a dead man get an erection? Is vaginal orgasm a myth? Why doesn't Viagra help women - or, for that matter, pandas? In Bonk, Roach shows us how and why sexual arousal and orgasm - two of the most complex, delightful, and amazing scientific phenomena on earth - can be so hard to achieve and what science is doing to slowly make the bedroom a more satisfying place.