As a child I read Sylvia Engdahl's "Heritage of the Star" (published as "The Star Shall Abide" in the USA). This was one of my most memorable reads ever, and earlier this year I was glad to find her sequels to the books and to read them through. I also discovered this nook which received some awards and was republished in 2001.
Having read the other books earlier this year, it was quite clear that this story exists in the same world as the others. It is in no way a sequel to "Heritage of the Star", but the galactic anthropological service is a key theme in the last book of that trilogy. The themes and ideas are all very similar.
The idea of a clash of civilisations at different stages of development is an intelligent and interesting one, and this book explores those themes well. The author explicitly states that the book is not allegorical for our times, but readers will see similarities with the story of "avatar" and thus with the clash of civilisations when Europeans came to the Americas (particularly the USA).
There are a few problems with this book though in my opinion. One is that having so recently read the other trilogy by this author, I was surprised and perhaps a little disappointed that it did not have more originality in setting. Add to this the galactic federation, and the multiple humanoid looking races, and this is a story that appears to be a product of the Star Trek age in which it was conceived. But that does not really detract from the ideas conveyed or the quality of the story.