Anxiety disorders are the most common mental health disorder among children and adolescents. We examined 111 treatment outcome studies testing 204 treatment conditions for child and adolescent anxiety published between 1967 and mid-2013. Studies were selected for inclusion in this review using the PracticeWise Evidence-Based Services database. Using guidelines identified by this journal (Southam-Gerow & Prinstein, 2014), studies were included if they were conducted with children and/or adolescents (ages 1-19) with anxiety and/or avoidance problems. In addition to reviewing the strength of the evidence, the review also examined indicators of effectiveness, common practices across treatment families, and mediators and moderators of treatment outcome. Six treatments reached well-established status for child and adolescent anxiety, 8 were identified as probably efficacious, 2 were identified as possibly efficacious, 6 treatments were deemed experimental, and 8 treatments of questionable efficacy emerged. Findings from this review suggest substantial support for cognitive-behavioral therapy (CBT) as an effective and appropriate first-line treatment for youth with anxiety disorders. Several other treatment approaches emerged as probably efficacious that are not primarily CBT based, suggesting that there are alternative evidence-based treatments that practitioners can turn to for children and adolescents who do not respond well to CBT. The review concludes with a discussion of treatments that improve functioning in addition to reducing symptoms, common practices derived from evidence-based treatments, mediators and moderators of treatment outcomes, recommendations for best practice, and suggestions for future research.