The examination was performed in two steps: screening of all personnel who had worked in Thailand using a questionnaire, followed by clinical examinations of persons reporting new or aggravated skin, airway or other health problems related to working in Thailand. General information about working conditions and exposure in Thailand was obtained from key persons among the Danish DVI Team and published literature [1, 2, 9, 10]. The clinical examination of screen positive included a structured interview on health history and exposure including the use of personal protection. A physical examination, and a standard lung function test was performed on all participants. Medical records were eventually requested. Individuals with skin disorders were clinically evaluated by a dermatological specialist and examined for type IV allergy (patch test) with European baseline series supplemented with specific chemicals. Persons with airway symptoms or a history of inhalation allergy had performed an extended lung function test including metacholin provocation, test of reversibility after beta-2-agonist and a skin prick test for ten standard inhalation allergens. A specialist in pulmonary medicine evaluated the findings. Causality was based on the following aspects (1) temporal association between the clinical disorder with the stay in Thailand, (2) a wellknown cause-effect relationship between the exposure and the disorder, and (3) results of the tests for allergy. Classification of causality included: (a) probably related, (b) possibly related, (c) no support of causal relationship, and (d) deterioration of a pre-existing disorder.