Anxiety is common and despite effective treatments, many youth go untreated. Dissemination work has focused on delivering services to children in schools. However, school teams cannot deliver clinical care at the rate that children need it and school nurses are well-positioned to intervene. Anxious youth present to their school nurse with somatic complaints. School nurses can identify anxious students but are not systematically trained in anxiety reduction skills. This study examined the fidelity with which nurses implemented evidence-based interventions for youth. Results showed that nurses were equally adherent and competence in delivering relaxation skills-based and cognitive behavioral therapy-based interventions. This study demonstrated that confidence impacted nurse fidelity. Additionally, nurse adherence, but not competence, predicted child outcome on anxiety. Results from this study highlight the importance of fidelity in intervention studies. This work helps begin to address gap in examining fidelity in school nurse interventions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]