Active pharmaceutical ingredients (APIs) and adjuvants of medications are often excreted unchanged (i.e. as active compounds) or as metabolites. It has been found that their removal during sewage treatment-if in place-has severe limitations and is often not sustainable. APIs may degrade incompletely in the environment thus resulting in numerous transformation products (TPs). Both parent compounds (PCs) and TPs are present in the environment. As so-called 'micro-pollutants' they may constitute a risk to the environment and the consumer. They represent a big obstacle for the sustainable management of water resources worldwide. Furthermore, testing and risk assessment will neither be possible nor affordable for all compounds, due to the sheer number of APIs but also the number of transformation products to be tested and identified. With respect to increasing population and increasing standards of living, the problem is likely to be more severe in the future. Therefore it is necessary to find solutions that prevent the input of pharmaceuticals into the environment from the very beginning of the design process. Developing new API molecules and adjuvants that are rapidly and fully mineralized after they leave the body is such an approach. This 'Benign by Design'-paradigm will not only contribute to a more sustainable pharmacy, it encourages the development of new products by encouraging innovation which will potentially widen its impact.