OBJECTIVES: When comparing patient management and patient outcomes, the available services within a catchment area appear to be a major confounding factor. The ESMS aims to classify services and measure their activity in a standardized way, which opens new opportunities to adjust for service offer. The ESMS allows to map the services available in a set of catchment areas and to identify different profiles. In addition we evaluate the accuracy of the French standardized classification of mental health services and the applicability of the instrument in France. METHODS: 171 services in 24 catchment areas were involved in the study, which focused on the French public mental health care system. Each service was classified according to the ESMS and data were collected on service use. The data for each catchment area were aggregated in residential use, structured day activities, continuous out patient care and emergency out patient care, then a cluster analysis was performed. The ESMS classification of the services based on function was compared to the official French description of services. RESULTS: Four classes were identified: Class 1 high activity in all services, class 2 low activity in all services, class 3 low activity in continuous ambulatory care, class 4 high activity in continuous ambulatory care. The ESMS confirmed the consistency between the French official description of the services' missions and the actual activity. 10% of the services had at least one additional “non official” function. The study showed that the ESMS was adapted for use in France, but it requires expert supervision for large-scale implementation. CONCLUSIONS: The ESMS proves to be useful not only in mental health service research, but can also bring the possibility to adjust for the catchment area's service profile in outcomes research.