The Cradle to Cradle (C2C) concept takes natural systems as a source of inspiration, striving toward a positive vision where human society and industry regard waste as “food” for new cycles of use, and are powered entirely by renewable energy. Cradle to Cradle is not about efficiency but about effectiveness—waste need not be minimized if it is food for other cycles, providing positive regenerative impacts. However, this is difficult to achieve in practice. The Circular Economy concept elaborates on the Cradle to Cradle model, prioritizing longer product lifetime and recovering whole products over material recovery through recycling.
The Circular Economy also combines ecological thinking with economic thinking, making a business argument for sustainability.
Both concepts have been very influential in shaping the way we think about design for sustainability.

Product service systems (PSSs) are revenue models where customers pay the company for the service the product provides, not (only) for the physical product itself.
Designing the revenue model along with the product can align economic incentives with environmental impacts, so the company has an incentive to design products for longer lives.
Both the company and the customer can benefit financially from longer‑lived products billed as services.
Not all product service systems are sustainable environmentally or socially, but if properly designed, they can greatly enable the circular economy.

The validity and reliability of four prevalent reparability scoring systems has been investigated by comparing scores of ten smart phones and six vacuum cleaners versus empirically measured repair times, as well as comparing hypothetical ideal and problematic scenarios. Ease of disassembly methods was also assessed for five smart TVs, four washing machines and six vacuum cleaners. The scoring systems studied were the French Reparability Index (FRI), Joint Research Centre Scoring System (RSS/JRC), iFixit, and ONR19202. Overall scores of products across scoring systems were relatively well correlated, indicating a fair amount of overall reliability. However, the variability in scores for the best and worst case of the same product was often larger than the differences between products. Validity was good for products that are easily repairable, but scorecards often failed to score low when repair is infeasible or too expensive. Repair scores greatly depend on disassembly; since some scorecards count numbers of disassembly steps and other scorecards use proxy times, these two methods were compared against empirical disassembly times for five vacuum cleaners, five televisions, and four washing machines. The proxy time method was found to be highly accurate for all three product categories; the steps method was less so. It indicated the relative ease of disassembly well for washing machines, but not for televisions or vacuum cleaners. Finally, this study proposes improvements to scoring methods, including a limiting factor approach and the development of clearer protocols, to ensure the scoring systems are robust, reliable, and can effectively guide sustainable product design.

The short lifespans and rapid innovation cycles of electronic products result in the loss of valuable and critical resources (Bakker, Wang, Huisman, & den Hollander, 2014; Baldé et al., 2024). Strategies aimed at extending product lifetimes, such as design for repair, focus on improving the ease of manual disassembly (De Fazio, Bakker, Flipsen, & Balkenende, 2021). However, connections optimized for repairability can hinder the mechanical separation of materials during recycling. This highlights a critical trade-off: improving repairability can often conflict with recyclability, emphasizing the need for balanced design approaches that address both recovery goals. Navigating these trade-offs requires a deeper understanding of how materials and connection types in electronics affect circular strategies. This research aims to investigate tensions between repairability and recyclability by analyzing a diverse set of electronic products and relating the findings to their design architecture. This study seeks to inform design strategies that optimize for both repairability and recyclability, thus prolonging product lifetime while minimizing resource losses at end-of-life.

The Business Model Canvas (BMC) is a fundamental tool for both understanding and creating or changing businesses. It diagrams costs, revenues, your customers, suppliers, and more, so you can make sure they all align. Normal BMCs only consider economic profit, but the Presidio Sustainability Booster adds environmental and social sustainability considerations for every part of the BMC. The Presidio Sustainability Booster is a qualitative and creative tool; it does not quantify whether one business model is better than another. The Presidio Sustainability Booster can help you assess an existing business, and/or help you generate ideas for improving a business.

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.