In the last decades, marine litter has become ubiquitous and has adverse impacts on marine animals through entanglement of mammals, reptiles, sea birds, fish and other animals in discarded and lost fishing gear and other plastic litter items, as well as through ingestion, especially of micro- and mesoplastics, by vertebrates and invertebrates (Figure 1). As part of a project embedded in the implementation of the Marine Strategy Framework Directive (MSFD), we were commissioned to analyze data from monitoring of marine litter, including microplastics, on beaches and in other compartments of the marine environment. Spatial and temporal trends should be identified, and results should be used to classify European marine waters according to their level of pollution with marine litter. Prior to evaluation, indicators of the Good Environmental Status (GES) should be defined, such as the existing OSPAR-EcoQO on the amount of plastic in the stomachs of northern fulmars. Finally for all marine compartments, recommendations for future monitoring of marine litter have to be given.