Radiocesium contamination of air, rain, grass, milk and humans in Belgium from the late 1950s to present was measured. The main sources of fallout were atmospheric nuclear weapons tests and the Chernobyl accident; in Belgium the average impact of the first on the human body burden was more than six times higher. The geographical distribution of radiocesium fallout in Belgium was surveyed by means of in-situ gammaspectrometry with HPGe detectors.