Attention-deficit hyperactivity disorder (ADHD) is comorbid with a range of other disorders, including anxiety disorders. The aim was to examine different explanations for the covariation of these symptom domains in children according to the framework provided by (Lilienfeld, S. O. Comorbidity between and within childhood externalizing and internalizing disorders: Reflections and directions. Journal of Abnormal Child Psychology, 2003). The covariation of ADHD symptoms and anxiety symptoms were examined over a 12-month period in a community sample of 499 children aged 8-13; 91% were retained at 12-month follow-up. Dimensional assessments were conducted using questionnaires given to children, parents and teachers, with results analyzed via structural equation modeling. Positive associations between ADHD and anxiety symptoms were linked with inattention symptoms, were particularly pronounced for girls, and were linked via temperament and behavioral problems. No support for the hypothesis that ADHD symptoms predicted the development of anxiety symptoms over time or vice versa. ADHD symptoms (particularly inattention) and anxiety symptoms are covarying phenomena that are linked with an irritable temperament and disruptive behavior.