It depends on how much of a glass fanatic you are. If you don't need it for use with these pieces, you can probably skip it. On the other hand, it is one of the very few places that Harrtil is shown with a photo and discusssed. As far as the rest of the book goes, when it was published, it was way ahead of its time, a masterpiece. Today, however, most of what is in it is available elsewhere, with better photos. Emphasis on MOST, however; if you're really a glass fanactic, there are juicy details in it that aren't available elsewhere.