I have been practicing Tai Chi for over 12 years and am always interested in good books on the subject. Unforunatley many texts simply repeat the same material and any forms illustrated tend to be the flavour of that particular author. So what you want is a smaller number of the best books that you can really get something from and trust. TT's insights and transalaion of the Tai Chi Classics is excellent, in fact its my favourite book on Tai Chi by far.The next book to this would be Douglas Wile's Tai Chi Touchstones The Yang Family Secret Transmissions. But TT's Book is perhaps the best on the classics he has a real clarity of understanding of the art and puts it across well. Outside of these core books look for general material on Taoism, Zen, & Mediation to broaden your practice. The last I heard a number of years ago TT was 99 is he still alive ? I would like to know.