A connection is generally assumed between occupational health care (in Dutch 'bedrijfsgezondheidszorg', or BGZ) and a reduction in absenteeism. In the Dutch literature various authors and researchers make great claims for the effect of occupational health care in reducing absenteeism. As yet, however, they have not concerned themselves very much with providing proof for the validity of their position. They speculate as to the positive influence of occupational health care on the health and welfare of employees and assume a direct connection between it and the reduction of absenteeism, but they do not have at their disposal empirical research results to support their speculations. So far as we know solid research of an experimental or quasi-experimental design into the relationship between occupational health care and absenteeism has never been carried out. Recently, however, an experiment with occupational health care for teaching personnel (in Dutch: Experiment met BGZ voor Onderwijspersoneel, or EBO) did take place, providing the opportunity to determine the influence of occupational health care on absenteeism in a quasi-experimental setting. Unfortunately, the results of the experiment indicate that the relationship between occupational health care and absenteeism is more complex than is generally assumed. In the course of the experiment, and in particular during the final year, the level of absence in the experimental group rose considerably, while in the control group it fell slightly. That rise was mainly due to the increase in the number of persons who were sick for a long period of time (at least 6 months).