Nowadays, the circular economy represents a promising strategy for achieving sustainable development through optimising resource efficiency, extending product lifespans, and reducing environmental impacts. Despite the growing interest in circular design practices, companies often face difficulties integrating these principles into their established New Product Development (NPD) processes. This is mainly due to the overwhelming number of available design tools and methods, which are fragmented, challenging to navigate, overlap in functionality, and lack standardisation. This study provides a comprehensive mapping, classification, and analysis of 77 existing circular design tools identified through a systematic literature review and supplementary online searches. The tools were systematically categorised according to format, data type, industry sector, circular strategies, innovation focus, aims, and applicability across the NPD stages. The results indicate a predominance of physical, qualitative, and sector-agnostic tools, emphasising circularity integration within the Discover, Define, and Develop phases of the design process. This structured classification facilitates stakeholder navigation of existing resources, highlighting opportunities for more targeted, industry-specific tool development, consumer-oriented approaches, and the importance of considering Industry 4.0 technologies in circular design practice. Future research could address these gaps by developing customised frameworks, validating tool effectiveness through real industrial applications, and promoting deeper integration of circular design tools within NPD practices and business objectives.

The depletion of fossil resources, increasing packaging pollution, and stricter regulations require the development of sustainable alternative materials. This study presents POMOPLA², a fully bio‐based composite that enhances circularity by valorizing industrial tomato peel by‐products within a plasticized polylactic acid (PLA) matrix. A novel bio‐based and biodegradable plasticizer derived from oils was used to successfully reduce PLA brittleness, providing higher toughness (+485%) and strain at break (+177%), a lower glass transition temperature, while enhancing the compatibility of the tomato peels, used as reinforcement. The incorporation of tomato peel biomass has the potential to reduce production costs, and we showed that it can be used to modulate mechanical performance as well as aesthetics‐sensory attributes. Low percentages of tomato peels (5% w/w) maintained translucency for flexible film packaging applications, whereas higher contents (20% w/w) proved adequate mechanical properties for rigid packaging. POMOPLA² might implement a local circular economy in line with the European Circular Economy Action Plan, that is, to produce tomatoes' packaging to be potentially reintegrated into the biological cycle as compost, fostering a seamless nature‐to‐nature cycle.