Occupational contact dermatitis is the most frequent type of skin diseases caused by occupational factors. The frequency varies considerably among professions and is highest in hairdressers, chefs, food handlers, and healthcare workers. Numerous irritants and contact allergens have to be considered in the pathogenesis and are often highly specific for a particular profession. Therefore, in-depth information on the working environment must be obtained for the diagnostic work-up. Careful patch testing, particularly with the worker's own materials, must be performed to identify relevant contact allergens. The prognosis depends on the diagnosis: slight forms of irritant contact dermatitis can usually be well improved with gloves and avoidance of major irritants. If an occupational contact allergen cannot be eliminated, or exposure to it be reduced, the worker frequently has to give up this occupation. Combined forms of allergic and irritant contact dermatitis, which are not rare, are the most difficult to treat. A multidisciplinary approach including dermatologists, allergists, technicians, and patient education is necessary.