Objective: To determine optimal Pediatric Anxiety Rating Scale (PARS) percent reduction and raw score cut-offs for predicting treatment response and remission among children and adolescents with anxiety disorders. Method: Data were from a subset of youth (N = 438; 7-17 years of age) who participated in the Child/Adolescent Anxiety Multimodal Study (CAMS), a multi-site, randomized controlled trial that examined the relative efficacy of cognitive-behavioral therapy (CBT; "Coping Cat"), medication (sertraline [SRT]), their combination, and pill placebo for the treatment of separation anxiety disorder, generalized anxiety disorder, and social phobia. The clinician-rated PARS was administered pre- and posttreatment (delivered over 12 weeks). Quality receiver operating characteristic methods assessed the performance of various PARS percent reductions and absolute cut-off scores in predicting treatment response and remission, as determined by posttreatment ratings on the Clinical Global Impression scales and the Anxiety Disorders Interview Schedule for "DSM-IV". Corresponding change in impairment was evaluated using the Child Anxiety Impact Scale. Results: Reductions of 35% and 50% on the six-item PARS optimally predicted treatment response and remission, respectively. Post-treatment PARS raw scores of 8 to 10 optimally predicted remission. Anxiety improved as a function of PARS-defined treatment response and remission. Conclusions: Results serve as guidelines for operationalizing treatment response and remission in future research and in making cross-study comparisons. These guidelines can facilitate translation of research findings into clinical practice. (Contains 1 figure and 3 tables.)