I was curious to read Master's book because I have been hypnotized several times myself - though in a therapeutic setting, not a sexual setting. I haven't yet tried the techniques outlined in Master's book (though I've passed my copy off to my partner and am curious to see where things go) but I can say, speaking from my own experience of being hypnotized many times, that Masters has written an excellent guide to hypnosis for the lay person. His instructions are clear and very detailed and he often explains the reasoning behind his instructions as well so that the reader will be able to confidently adapt the techniques for individual situations. Masters even covers many of the "glitches" I personally experienced as a hypnosis subject and explains ways to avoid or minimize those situations.
Masters spends a good amount of time explaining the ethics of hypnosis. This is very important since hypnosis requires a good amount of trust and is an activity that can be abused by the unscrupulous. Despite the possibility for abuse, however, Masters makes certain to point out that hypnosis cannot force someone to do things that they wouldn't otherwise be willing to do. This is not a book for someone who wants to trick people into going to bed with them or force people to do things against their will. This is not a book of techniques to save a failing marriage. Hypnosis is about enhancing what is already there, lowering inhibitions against following one's inherent desires, helping one to gain the courage to explore one's desires more closely and so on. The author does not come across as preachy when discussing ethics and his writing style makes it interesting to read what might otherwise be a dry topic.
The reader should expect to spend a lot of time and effort implementing the ideas in this book. This is not a book one just reads and then sets down and is done with -- to get the most out of this book, one has to be willing to work on the exercises. Progress is slow as Masters wisely advises couples to take their time getting into hypnosis. In fact, Masters strongly suggests that the first session consist only of hypnotizing one's partner, checking to see if they are in a trance, bringing them back out of the trance and talking about what happened. Don't expect to be able to read this book in the afternoon and then have fully hypnotized active sex that evening unless you are already an expert hypnotist and your partner is already a proven subject with whom you have worked before. If you want an instant sex toy, get a new vibrator. This book is for people who are willing and able to put a lot of effort and time into building creative and vibrant sex play.
For those interested in using the ideas in this book professionally (such as dominatrices and other sex workers), Masters offers sufficient information and advice that is readily adapted to a professional setting including a short section about the BDSM applications of hypnosis. He also covers what sort of people should most definitely not be hypnotized and workers can use this information for screening purposes to "risk out" those for whom hypnosis play would be more dangerous than erotic.
One of the most valuable aspects of this book, in my opinion, is the copious inclusion of scripts. When I think about hypnotizing a partner, my biggest fear is that I will not know what to say or not remember the best ways to phrase ideas. Masters includes scripts for inducing hypnosis, scripts for dealing with various hypnotic situations and even suggested scripts for sexual fantasy play. Of course many of these scripts should be modified so that they more accurately fit individual situations. A really dedicated reader could even type out the scripts with appropriate modifications and print out their own personal scripts for play sessions.
I found this to be an excellent book and clearly written. I am eager to begin working with the techniques to add a little extra spice to bedroom play between my partner and myself and recommend this book to anyone who wants to add some adventure and mystery to their sex life.