It is unclear why the authors discuss only certain instruments that measure anxiety or specific disorders and even less clear why certain instruments were selected for inclusion. For example, the Fear Questionnaire is described, but not the Fear Survey Schedule; the Gambrill and Richey Assertion Inventory is included as a measure related to social anxiety, but the Liebowitz Social Anxiety Scale is not. Similarly, the list of sites where professionals can find training is incomplete. Aside from any number of other institutions that provide training, there are national organizations that provide workshops and training institutes—for example, the Anxiety Disorders Association of America, the Association for the Advancement of Behavior Therapy, and the Obsessive-Compulsive Foundation.