Recently I had to use FrameMaker as authoring tool for DoocBook, it was quite a challenging task because it required learning a lot of new stuff. FrameMaker is a powerful and sophisticated tool, with XML capabilities that were build on top of its SGML legacy, so it's a pretty complex beast to learn. This book was just right on the spot; it allowed me to save an outrageous amount of time and frustration. I don't know if it can be valuable for seasoned FrameMaker users, but I am sure it's a great investment if you have to deal with FrameMaker and XML starting from scratch