The report “Plastic and microplastic in the environment” is a summary review of Austrian studies and activities dealing with the pollution of the environment caused by plastic and plastic particles. The report contains information about the investigation of plastic debris in the flow of the Danube River in Austria and discusses pathways into the environment. Ninety percent of the plastic debris are emitted by diffuse sources, these being littering, fragmentation, transport by wind, run-off from sealed surfaces, inappropriate use of products or construction activities. By the same pathways, plastic and microplastic can reach soil, air and other environmental compartments and finally the food chain. The report concludes with recommendations how to tackle the challenge of reducing plastic and microplastic contamination in the environment.