This book covers DBT and ACT as treatments for depersonalization disorder, which, as other reviewers have pointed out, are not evidence-based treatments for this condition. As far as I could tell, the authors were making an argument for this treatment largely based on three case studies. And disappointingly, I don't even remember the people from the case studies reporting any decrease in distress or symptoms. There was also something about their tone I also found a little dismissive - their attitude was more or less "these people need to learn skills to suck it up and stop malingering in therapists/doctors offices." It's true that the disorder can spontaneously or gradually disappear, but not for everyone, and this book did not convince me that this is the right treatment either way. Not recommended.