Much work has been done to develop and evaluate approaches to the treatment of behavioral and emotional disorders in children and adolescents, in general (e.g., Hibbs & Jensen, 2005; Kazdin & Weisz, 2003) and of anxiety disorders in youth, specifically (see Velting, Setzer, & Albano, 2004). One such approach, typically labeled "cognitive-behavioral therapy" (CBT), represents an integration of strategies that have a research basis. For example, exposure tasks in CBT address behavioral avoidance, a primary feature of anxiety, whereas cognitive training targets the cognitive misinterpretations and attentional biases found in anxious youth. Thus, CBT can be considered an empirically based approach: The components of the treatment target data-based aspects of the disorder. In addition, CBT has been subjected to randomized clinical trials (RCTs) to rigorously evaluate treatment outcome. The literature now contains a sufficient number of RCTs, conducted with clinical cases, in several countries, and with reasonably consistent and positive outcomes reported by multiple teams of investigators. Given the body of empirical support that has been reported, and in sync with the evaluative reviews of others (e.g., Kazdin & Weisz, 1998; Ollendick, King, & Chorpita, 2006), CBT has been included among those treatments referred to as an empirically supported treatment (EST), and more specifically can be considered a "probably efficacious" treatment (see also Albano & Kendall, 2002). Achieving the status of an EST is an accomplishment, but the set of necessary treatment outcome evaluations for CBT have not yet been completed. The data to date are sufficiently encouraging, but the distance to be traveled is further than the distance traveled thus far. What is needed, and hence the motivation for this special issue, is a scholarly yet applied consideration of how to facilitate the further development and deployment of CBT for anxiety in youth. Toward this goal, we briefly mention issues in and ideas for dissemination, opportunities for the proper individualization of treatment, and features of the multicomponent nature of the treatment. The broader discussions appear in the articles that follow. It is worth noting that the authors are associated with the Child/Adolescent Anxiety Multimodal Study (CAMS), a multisite study comparing the relative efficacy of CBT, medication (sertraline), the combination of these approaches (combined treatment), and a pill placebo condition.1 Participants ages 7 to 17 must meet the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for generalized anxiety disorder (GAD), social phobia (SP), and/or separation anxiety disorder (SAD), with relatively few exclusionary criteria. Across 12 weeks, CBT therapists in CAMS provide 14 sessions of CBT. FLEXIBILITY WITHIN FIDELITY: AN IDEAL DISSEMINATION When critics of manualized treatments assume that adherence to a manual requires rigid and inflexible applications, they may be legitimately resistant to using a manualized approach. However, the truth is that manuals are not rigid and there is indeed a desired place for "flexibility within fidelity" (Kendall, 2001; Kendall & Beidas, in press). Authors of the set of articles in this special issue will mention treatment manuals and discuss clinical experiences with the intent of communicating the common clinical features of implementing a manual-based EST. Flexibility has a place, but it is worthwhile to consider how and where to be flexible. For example, the exact application of therapy procedures may vary from client to client, but the underlying principles (see Gosch, Flannery-Schroeder, Mauro, & Compton, this issue) remain largely the same. Understanding the underlying principles that are consistent across cases facilitates the flexible application of manualized treatments. Age is often used as the easy marker for maturation. …