A few years ago, I came around to Yohan's way of thinking and decided that NO book is vital to a JKD library. I actually sold mine on eBay. It had all the usual suspects. The Tao of JKD, the DeMile book on the 1" punch, the Fighting Method books, some Vunak stuff, etc. In the end, I decided that purchasing and perusing the books could easily become a substitute for the actual experience of training. And that I wasn't really gaining anything from accumulating information I 1) already had or 2) didn't need. The only things I kept were written by Guro Dan. Because Guro Dan is rewarding to read in his own right.