Although cognitive behavioral therapy (CBT) has been found to be efficacious in the treatment of child anxiety disorders, little progress has been made in the dissemination of such treatments to real-world practice settings. Clinical trials conducted in practice settings can demonstrate the degree to which evidence-based treatments are appropriate for larger scale dissemination. This study evaluates CBT as a treatment for child anxiety disorders in the elementary school clinic setting. A randomized, controlled trial design has been employed, comparing immediate treatment and a three-month waitlist. The trial is being conducted in several Los Angeles area elementary schools and is only available to children in these particular schools. To ensure that the CBT intervention is flexible and capable of matching the characteristics of various school settings, clinicians, and referred children, a modular treatment approach is employed. The study design includes elements to ensure high quality data, such as the use of independent evaluators and tests of treatment fidelity. Children, ages 5 to 12 years, are referred by teachers and staff or are identified as having high anxiety in concurrent studies. All participating children have DSM-IV diagnoses of separation anxiety disorder, generalized anxiety disorder, or social phobia, according to a semi-structured diagnostic interview. Therapy and clinical supervision is provided by the research team. It is hypothesized that children receiving immediate treatment will have significantly lower anxiety scores than children assigned to the waitlist at the posttreatment/postwaitlist assessment. If results are favorable, further exploration of dissemination of CBT into school clinic settings may be indicated.