This is a beautiful book. It is geared toward older children, but the presentation and photo quality will make any adult take a second look. Klimt's work is often characterized by the use of gold leaf -- this book actually prints the paintings so that they have a gold surface. Each page discusses an aspect of Klimt's life or work-- his relationship with Emile Floge, his travels to Italy, his Beethoven Frieze, etc. The background of each page is beautifully decorated to correspond with the information and photographs.
I have several other books of Klimt's work-- this one has the best overview of his life and work, best reproductions, and by far my favorite in terms of how it presented the information. It is only 30 pages, but is truly a gem of a book.
If you are interested in art history or art in general, I also recommend the other Adventures in Art books, particulary the one on Van Gogh. The presentation is very similar to the Klimt book.