This book is so good that I bought 4-5 copies and gave them to friends. I am a biologist in graduate school but read this as an undergraduate. If I hadn't already been interested in biology, this would have done it for me...but it just poured fuel on the fire for me.I really really highly recommend this book for a layperson or someone with some existing knowledge who wants to get a summarization of many concepts in sex (in the biological sense). Please see my response to Eris's review for an alternate opinion on the book that is much more extensive than this blurb.