The Protodynastic Period was the last era of Egyptian prehistory, the Naqada III period, which lasted maybe two centuries. It was a period of rapid change that ended with the unification of Egypt under the pharaohs. We have a lot of evidence about it, but it's hard to pull that evidence into a coherent picture of what happened. Therefore, Shire Egyptology's treatment of Egyptian prehistory is split into Predynastic Egypt, covering many millennia, and this book, zooming in to focus on those crucial last centuries.
This book is in the same vein as its predecessor. It can't treat the subject very thoroughly with so few pages, and it spends a lot of time describing artifacts rather than analyzing large trends. Yet when it does turn to those trends, it is good at describing the uncertainties and disagreements surrounding them. I'm not especially knowledgeable about the Predynastic Period, but I haven't spotted any outdated facts in this 20-year-old booklet.
Get this book and its companion if, for some reason, you want to learn about the Predynastic Period but need very little detail. If you want more, look for Egypt Before the Pharaohs or The Prehistory of Egypt.
The supplied chronology is almost useless for the period under discussion. The map is alright but omits most of the wadis mentioned. There are several terms used without adequate explanation - Thinite, Master of Animals, Heb-sed, etc - which necessitates further reading elsewhere. Some of the pages are solid blocks of text without paragraph breaks. This book is by no means an easy read, but the authors fairly and freely admit the lack of consensus on many subjects - so the book appears to be an honest appraisal of current knowledge - in 1997.