Implementation of a Quality System in accordance with the ISO 9000 standard with an Occupational Health Service. Following the lead of the industrial sector, Quality Systems (QS), in accordance with the principles of the ISO 9000 standards, have been implemented in many health care organizations. The purpose is to improve the health care delivered to the patient in a systematic way improving the system efficacy and effectiveness. Our aim is to describe a practical approach for the implementation of a QS in accordance with the ISO 9000 standard within an Occupational Health Service (OHS) in a middle-sized hospital. The purpose of the system is to ensure that everyone at the OHS is aware of the common quality objectives and knows how to act in order to achieve them. The implementation of the QS has entailed 2 phases: (i) a conformity assessment to verify that the organization and services delivered measure up to ISO standards; (ii) the development of a deployment plan to support the activities and action implementation for achieving the QS requirement of ISO 9000. An early conformity assessment highlighted the need for management and control in order to assure quality. The Service did not have a documented QS, a documented management review and a documented procedure for corrective and preventive actions for ensuring QS implementation and its effectiveness. A strategic quality plan, focused upon the major areas for improvement, was developed. This practical approach shows encouraging results because it allows to build up the basic quality and to motivate the OHS personnel.