Overviews of systematic reviews (OSRs) provide rapid access to high quality, consolidated research evidence about prevention intervention options, supporting evidence-informed decision-making, and the identification of fruitful areas of new research. This OSR addressed three questions about prevention strategies for child and adolescent anxiety: (1) Does the intervention prevent anxiety diagnosis and/or reduce anxiety symptoms compared to passive controls? (2) Is the intervention equal to or more effective than active controls? (3) What is the evidence quality (EQ) for the intervention? Prespecified inclusion criteria identified systematic reviews and meta-analyses (2000–2014) with an AMSTAR quality score ≥ 3/5. EQ was rated using Oxford evidence levels EQ1 (highest) to EQ5 (lowest). Three reviews met inclusion criteria. One narrative systematic review concluded school-based interventions reduce anxiety symptoms. One meta-analysis pooled 65 randomized controlled trials (RCTs; any intervention) and reported a small, statistically significant reduction in anxiety symptoms and diagnosis incidence. Neither review provided pooled effect size estimates for specific intervention options defined by type (i.e., universal/selective/indicated), intervention content, or comparison group (i.e., passive/active control), thus precluding EQ ratings. One meta-analysis pooled trials of vigorous exercise and reported small, nonstatistically significant reductions in anxiety symptoms for comparisons against passive and active controls (EQ1). Better use of primary studies in meta-analyses, including program-specific pooled effect size estimates and network meta-analysis is needed to guide evidence-informed anxiety prevention program choices. RCTs of innovative community/primary care based interventions and web-based strategies can fill knowledge gaps.