OBJECTIVE The identification of reliable quality indicators (QIs) is a crucial step in enabling users to quantify the quality of laboratory services. The current lack of attention to extra-laboratory factors is in stark contrast with the body of evidence pointing to the multitude of errors that continue to occur in the pre- and post-analytical phases. METHODS Different QIs and terminologies are currently used and, therefore, there is the need to harmonize proposed QIs. RESULTS A model of quality indicators (MQI) has been consensually developed by a group of clinical laboratories according to a project launched by a working group of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). The model includes 57 QIs related to key processes (35 pre-, 7 intra- and 15 post-analytical phases) and 3 to support processes. CONCLUSIONS The developed MQI and the data collected provide evidence of the feasibility of the project to harmonize currently available QIs, but further efforts should be done to involve more clinical laboratories and to collect a more consistent amount of data.