Allergy-testing is a prerequisite for specific allergy treatment, including specific allergen avoidance measures, relevant pharmacotherapy and specific allergy vaccination. All children with persisting, recurrent or severe possible "allergic symptoms" or those with a need for continuous treatment should be tested, irrespective of the child's age. Allergy-testing includes a careful case history and a determination of IgE sensitisation by skin prick test or the measurement of allergen-specific IgE in serum by standardised and validated methods. The diagnosis of food allergy cannot usually be based solely on the case history and IgE sensitisation; the diagnosis has to be confirmed by controlled food elimination and food challenge procedures. The diagnosis of inhalant allergic disease requires only confirmatory nasal, conjunctival or bronchial challenges in equivocal cases or before specific allergy treatment such as extensive allergen avoidance measures or allergy vaccination.