Little is known about the contribution of technical and relational factors to child outcomes in cognitive behavioral therapy (CBT) for children with anxiety disorders. This study investigated the association between treatment adherence, the child-therapist alliance, and child clinical outcomes in manual-guided individual- and group-based CBT for youths diagnosed with anxiety disorders. Trained observers rated tapes of therapy sessions for treatment adherence and child-therapist alliance in a sample of 52 children (aged 8 to 12) with anxiety disorders. Self-reported child anxiety was assessed at pre-, mid-, and posttreatment; parent-reported child internalizing symptoms was assessed at pre- and posttreatment. The results showed high levels of treatment adherence and child-therapist alliance in both CBT programs. Neither treatment adherence nor child-therapist alliance predicted traditional measurements of child outcomes in the present study, but a relation between alliance and outcome was found using a more precise estimation of the true pre-post differences. Implications of these findings for expanding our understanding of how treatment processes relate to child outcome in CBT for children with anxiety disorders are discussed. (Contains 5 tables.)