peer reviewed ; The development of a plant health barometer, an instrument to measure the general phytosanitary situation on a national level (Belgium) and on a yearly basis and to monitor its evolution over time, is described. The elaboration of a set of 13 plant health indicators (PHI’s) as the basis for the plant health barometer is discussed. These indicators were weighted by experts - including scientists, policy makers and agroindustrial representatives - to determine their relative impact in the barometer. The result of the barometer is expressed as a comparison with the previous year. Based on the results of the 13 PHI’s, it is concluded that the general plant health in Belgium shows a positive evolution from 2007 until 2010 and a negative evolution from 2010 until 2012. The plant health barometer provides a overview of the phytosanitary situation of plants and plant products in Belgium and is a tool to communicate in an intelligible, comprehensible manner on aspects of plant health to consumers and professional stakeholders in the plant production chain. Together with the food safety barometer and the animal health barometer, the plant health barometer is one of the three instruments to provide a overview on the general status of the safety of the food chain in Belgium.