The aim of this Document is to define the general outlines for the qualification of legal metrology officers and to suggest models for training programs for this profession. The training and qualification is set up in a modular structure, which allows each country to arrange tailormade training programs according to the preconditions and the specific needs (qualification on demand). This Document is not concerned with technicians responsible for the metrological control of production in all industrial sectors, technicians in charge of maintenance of measuring instruments or technicians employed to help engineers and research workers in research laboratories and basic metrology laboratories, but it is evident that many of the subjects included in the study program could also be useful for such technicians.