Occupational nasal allergies caused by moulds and wood dust were extensively studied in six wood furniture factories. The concentration of moulds, wood dust and endotoxins was registered and occasionally high values were found. Paecilomyces spec. was the most common mould. Answers to a special questionnaire showed that 16% (42/268) of the wood workers with a mean exposure time of 12 years had a history compatible with hypersensitivity in the upper airways associated with their work. Calculations based on skin prick tests and provocation tests with relevant allergens showed that the wood furniture workers had an incidence of allergy to moulds in 3% and to wood dust in 2%. Most of the workers (5/7) sensitive to moulds and/or woods were also skin prick sensitive to other allergens. No statistical difference concerning the presence of precipitating antibodies against mould and wood antigens could be registered between workers with discomfort and workers without symptoms.