Because of the complexity of many environmental problems, we need their holistic assessment. That is why, in such a matter, a multidisciplinary approach is necessary. It has also been the guiding line for this present study on the European regulation of the GMOs, crossing the different points of view of a lawyer and a biologist. According to the European legislation, molecular biology and dissemination of genetically modified organisms are mainly regulated by two major directives of the European Parliament and of the Council: Directive 2009/41/EC on the contained use of genetically modified microorganisms, and Directive 2001/18/EC on the deliberate release into the environment of genetically modified organisms. Two different approaches are possible to analyse those directives and suggest possible improvements.