The objective of this study is to evaluate the psychometrics and clinical efficiency of the Multidimensional Anxiety Scale for Children (MASC), which measures physical symptoms, harm avoidance, social anxiety, and separation/panic. Using a sample of 190 treatment-seeking Norwegian youth (aged 7-13 years, M[subscript age] = 10.3 years, 62.1% male), the internal stability and ability to predict to disorder were examined for child, mother, and father reports on the MASC. Moderate to strong internal reliability was exhibited across all MASC subscales. Parent-child agreement was low, but mother-father agreement was high. MASC scores successfully distinguished between children with and without anxiety disorders and identified youth with separation anxiety disorder and social phobia, but less accurately generalized anxiety disorders. The MASC has favorable psychometric properties and is a useful screening instrument for identifying youth with anxiety disorders. (Contains 6 tables and 3 footnotes.)