The objective of taking occupational history is for occupational medicine practitioners to find out about the relevant factors from the patient’s work environment which may have a detri­mental effect on humans and are known to have a causative association with various diseases. Extensive data on the used technological work processes and operations, harmful occupa­tional factors, work conditions, the rhythm of work and work regimen, use of general and personal protective equipment, hygienic conditions at work etc. are essential for determin­ing the diagnosis and proper treatment, as well as for selecting prophylactic activities. Data from a patient’s occupational history that are related to potential occupational risks refer not only to the patient’s current profession, but to all activities performed during his/her years of service (i. e. any potential late or delayed effects of harmful occupational factors also need to be taken into account). With respect to occupational diseases, the confirmation of clini­cal presentation, functional impairment and organ morphology also necessitate special pro­cedures that are not used in the diagnosis of other, non-occupational diseases. The diagnosis always needs to be confirmed with a diagnostic method which can objectively verify health impairment (the degree of which may also be expressed using a quantitative index). In some occupational diseases, the diagnostic procedure does not differ because of occupational caus­es (i. e. the impairment is verified in the same way, irrespective of whether occupational or non-occupational factors are involved), while in others the diagnostic procedure is highly spe­cific and is characteristic only of such diseases (e. g. confirmation of association between devi­ations of evaluation parameters and occupational exposure). For this reason, it is very important for the selected personal physician, as well as for all other physicians who come into contact with the patient and may express a suspicion of occupational etiology of his/her disease based on an exhaustive medical history and clinical presentation, to be well aware of the specificities of occupational history. Such a suspicion can be subsequently confirmed or rejected by an occupational medicine specialist by performing a more detailed study of the patient’s work environment.