This is a compendium of various divination and healing practices from native peoples (mostly from Africa). Some of the articles have been (almost verbatim) published in other compendia (such as the article by Edith Turner on the Ndembu) and others are mostly irrelevant (such as Devisch's naive psychoanalyzing of the Ngoombo). Ditto for Winkelman's naivete with respect to brain function, serotonin transporters and shamanism. For these guys shamanism is just a form of self-hypnosis.
Overall, the anthropology here is uneven, cautious, with the authors never capable of escaping the straight-jackets of the mainstream discipline . In fact, with the exception of Winkelman, who thinks 'spirits' are just a facet of brain ativity, none of the authors dares to tackle the question of the 'spirits' directly - even though spirits and ancestors are what shamanism is all about. This makes the book outdated even before it hit the shelves.
In my opinion, this book displays quite clearly the limitations of doing anthropology by "impartial observers". When it comes to academic shamanism, we are still in the dark ages.