Currently, the negative environmental effects of non-biodegradable conventional plastics are in the focus of the public discussion. Biodegradable plastics represent a valid alternative, offering new end of life options and a reduced environmental impact. Nevertheless stakeholders (e.g. politicians) ask the question: based on scientific evidence, is it possible to undoubtfully prove that biodegradable materials are truly biodegradable? Some years ago BASF has started a scientific journey to give an answer to this question. Together with partners, such as ETH Zürich and HYDRA Marine Sciences Institute, BASF started investigating in a systematic and fundamental way the biodegradation process of biodegradable plastics in different environments: industrial and home composting, anaerobic conditions, soil, limnic and marine habitats. The presentation will give an overview of the scientific methods developed so far to understand the interaction between materials, abiotic and biotic (microbes, enzymes) factors and the correlation between laboratory test and field trials.