Since the 1950s the amount of plastics in the marine environment has increased dramatically. Worldwide there is a growing concern about the risks and possible adverse effects of (micro)plastics. This paper reflects on the sources and effects of marine litter and the effects of policies and other actions taken worldwide. Current knowledge offers a solid basis for effective action. Yet, so far the effects of policies and other initiatives are still largely insufficient. The search for appropriate responses could be based on possible interventions and profound understanding of the context specific factors for success. Moreover, the scope, timeframe and dynamics of all initiatives are distinctly different and orchestration at all levels, in close cooperation with one another is currently lacking.

自1950年代以来，海洋环境中的塑料数量急剧增加。在世界范围内，人们越来越关注（微）塑料的风险和可能的不利影响。本文反映了海洋垃圾的来源和影响，以及全球范围内采取的政策和其他行动的影响。当前的知识为有效的行动提供了坚实的基础。但是，到目前为止，政策和其他举措的效果仍然很大。寻找适当的对策可以基于可能的干预措施以及对成功的具体背景因素的深刻理解。此外，所有举措的范围，时限和动态都明显不同，而且各个层次的编排工作目前缺乏相互密切的合作。