It is important to be able to monitor genetically modified (GM) crops, not only in the field but also during the food processing chain. New research shows that products from genetically modified crops can be identified at low concentration, using bioluminescent real time reporter (BART) technology and loop mediated isothermal amplification (LAMP). The combination of these techniques was able to recognize 0.1% GM contamination of maize, far below the current EU limit of 0.9%.