STOPP aims to STOP the ways that lead to environmental pollution, use of unsustainable virgin fossils, excess use of resources, high levels of generated plastic waste, incineration and landfilling, and climate change. We aim to do this by producing strategies for circular food plastic packaging with Refuse, Reduce, Redesign, Reuse and Recycle approaches. Our goal is to enhance sustainable and circular use of plastic food packaging and decrease the amount of generated waste while reducing the environmental impact. This is achieved via development and implementation of circular strategies together with an extensive network of plastics packaging value chain stakeholders, and citizens and consumers. Increased knowledge on the environmental and climate impacts of food packaging systems is a key driver in changing perception of reuse and recycling. We will quantify the effect of littered plastic food packaging on the environment with analysis of different ecosystems, biological organizational levels and key sentinel organisms. This deeper understanding is an important part together with different state-of-the-art and comprehensive enablers and barriers analysis for the technological developments, business strategies and consumer studies done in the project. Our technological approaches for reuse focus on safe and high-performance material development, improving return logistics, and developing consumer-centric communication strategies. For recycling, we will optimize collection systems, create safe food contact polyolefin recyclates, recycle bio-based and smart food packaging, and expand Plastics Recyclers Europe’ RecyClass certification scheme for recyclability. STOPP has a key role in supporting the Packaging and Packaging Waste Regulation implementation in its early stages via the developed novel solutions, providing new open access knowledge and hands-on tools for the value chain actors to start-up their sustainable circular food packaging journey as early adaptors.