This book provides a comprehensive and most recent discussion of breakthroughs on additive manufacturing for plastic materials recycling to boost a circular economy. It offers new ideas of combining/hybridizing processing methods that work as a source of information for manufacturers in making new and strategic product development plans. Additive Manufacturing for Plastic Recycling: Efforts in Boosting A Circular Economy provides a critical, comprehensive, methodological, and strong state-of-the-art of the past work on the processing of thermoplastic and thermosetting along with new directions and applications. It describes the common and hybrid approaches of recycling processes and includes theoretical and practical ideas of combining/hybridizing processing methods with the use of fused deposition modelling, which is one of the low-cost additive manufacturing techniques. The book discusses mechanical twin-screw extrusion followed by case studies for developing hybrid composite structures for biomedical and structural applications. Recent innovations in melt processing for recycling and the fundaments, process parameters investigations, and applications for new product development are also presented. This book is a first-hand reference source of information for academic scholars and commercial manufacturers for making strategic development plans on new product developments.