I am a final year Clinical Psychologist in Training and have referred to this book a number of times to guide my Cognitive Behavioural interventions with children. As an overview of effective Cognitive Behavioural Techniques for children and adolescents I think it is extrememly helpful. Moreover, there are few other books that offer similar coverage of the topic in a way that is so readily applicable to clinical practice.
I think the lack of reported efficacy of the treatments reflects the fact that this is a relatively new area and there have been far fewer treatment trials than in the adult CBT arena. I'm not sure that there is reason to be pessimistic quite yet. Most of the interventions reported in the book do have a sound empirical basis behind them.

Although I have not yet used cog-B interventions when working with children or adolescents, I was ready to be "wowed" by the information put forth by this book. However, the information that was conveyed was very disappointing. In the sections that dealt with externalizing and internalizing disorders, the gist of the information that was presented was that while cog-B tools often have the potential to be helpful, the research has not resulted in very inconsistent results. Therefore, the research puts into question both the efficacy of cog-B and point of using cog-B in the first place. Another fault of this book is that the chapter authors often point out aspects that are important to take into consideration such as the influence of developmental milestones and the family on a child, but then they fail to elaborate on these aspects.