This is a slim book, but manages to pack in chapters on many topics related with the subject matter. The book begins by asking whether you should take up consultancy at all. According to the sleeve notes the author has been a consultant for 25 years, so he should know what he is talking about - and I would assume that he would count himself as "successful", having remained one for such a length of time. The book begins by almost trying to put most people off the idea. He describes with an authoritative manner a list of skills you must have in order to become a consultant - and suggests that if you are not above average in all of them you should question whether it is a good career move.
The rest of the book is taken up with a series of how-tos that deal with different areas that could cause problems - such as what to specialise in, finding customers, planning, marketing and so on.
The book is written in an easy to read style, although the cartoons scattered throughout the book don't add anything and in my opinion should have been omitted. Much of the advice in the book is fairly high level and I would class some of it simply as common sense. There are several places that go into a little more depth, such as when describing different kinds of charts used for planning and project management. However in a book of this nature it is difficult to go into more detail since everyone's situation will be different.
All in all, an interesting book, with some useful information. I wouldn't class it as essential reading (as the back cover suggests) for all potential consultants, but I would certainly recommend a look.