BACKGROUND: The number of patients with atopic dermatitis is increasing., AD in industrialized countries concerns 5 to 20 % of children between 6&7 years old, of which nearly 10% still suffer from this disease during adulthood. Consequently; atopic dermatitis has become a true public health concern with namely difficulties in diagnosis and patient’s management. OBJECTIVES: In order to rapidly and effectively refer patients with AD to dermatologists or paediatricians, our work has aimed at designing and validating a questionnaire of presumed diagnosis of AD METHODS: This questionnaire  was designed and based on a large review of international scientific literature, in particular from articles about diagnosis criteria by Hanifi and Rajka and the UK Working Party, interviews of experts and a series of structured interviews of patients with AD of different levels of severity, hence forming a rich and structured verbatim. RESULTS: A questionnaire, using simple vocabulary, and comprising 20 questions, has been designed.  Answers to each question are dichotomic; the subject answering either « yes » or « no », so as to prevent any confusion. During test phase, it was found necessary to add « do not know »as a possible answer. 8 questions focus on the medical history of the patient and his/her family (parents and brothers/sisters),  2 questions dealt with difficulties in getting to sleep as well as the quality of sleep, 9 questions looked into the skin condition, and one question described the localization of possible lesions on the skin. Moreover, a psychometric validation has enable to confirm the internal consistency and very good reproducibility of the questionnaire CONCLUSIONS: The ongoing validation study carried in several dermatology hospital units will allow to determine 3 levels of presumed diagnosis of Atopic Dermatitis: « unlikely », « likely» or « possible »; which will help the caregiver decide whether the patient should be referred to a dermatologist to get appropriate treatment.