Health practitioners and decision makers in the medical and insurance systems need knowledge on the work-relatedness of burnout. To gather the most reliable information regarding burnout diagnosis and recognition in Europe, we used an 8-item standard questionnaire sent by e-mail to occupational health specialists identified via the Network on the Coordination and Harmonization of European Occupational Cohorts (OMEGA-NET) within the European Cooperation in Science and Technology (COST) Action. Participation rate was 100%, and the questionnaire was completed for 37 countries. In 14 (38%) countries burnout syndrome can be acknowledged as an occupational disease. However, only one country included burnout on the list of occupational diseases. The results showed a high variability in burnout diagnosis, in assessment of its work-relatedness, and in conditions allowing compensation of patients. These results reflect a lack of graded evidence on burnout and its determinants. The ongoing research on burnout conducted in the frame of the OMEGA-NET COST Action should be helpful through facilitating standardization of both existing and new data on burnout, a priority outcome requiring harmonization.