Fluidised bed reactors are in common use in the chemical industry and for generating electricity. A relatively recent application is the combustion of biomass to produce what is called Green Power. The thing about fluidised bed reactors is that they can be used in a wide range of production processes and they have excellent heat transmission.In the late 1980s chemical engineer Prof. Ir. Cor van den Bleek came to be regarded by his colleagues as a bit unconventional, to put it mildly, for proposing to use the chaos theory to solve problems in fl uidised bed reactors. Today Dr. Ir. Ruud van Ommen and Ir. John Nijenhuis have managed to build on the disparaged theory to develop a detection system giving operators of chemical plants and power stations early warning of impending reactor errors, thus avoiding much inconvenience and cost. In medicine too, applications have been found for the 'chaotic' technique. The fi rst product has already hit the market.