This study addresses what competencies (knowledge, skills, and attitudes) designers need in order to successfully design products and services for a circular economy. Existing literature, though sparse, has identified a number of circular economy competencies for design. Yet, a coherent overview is lacking. To complement the competencies found in the literature with insights from practice, we conducted 18 semi-structured interviews with design professionals. Our study identifies seven circular economy competencies for design: (1) Circular Impact Assessment, (2) Design for Recovery, (3) Design for Multiple Use Cycles, (4) Circular Business Models, (5) Circular User Engagement, (6) Circular Economy Collaboration, and (7) Circular Economy Communication. We used a general sustainability competencies framework to categorize our findings. Interestingly, we did not find evidence of the Systems Thinking competency in practice, although in the literature it is mentioned as a relevant competency for design for a circular economy. In addition, we found that methods and tools are still largely lacking or in a premature stage of development. We conclude that design for a circular economy can be seen as an upcoming, independent field within the sustainability domain, and that requires a specific set of competencies, methods, and tools. Our overview of circular economy competencies for design can guide the development of relevant methods and tools, circular economy-based design curricula, and training programs in the future.

In the transition to a circular economy companies are exploring new business models, implying a shift from selling products to offering products in circular business models, such as leasing. Product design is thought to play a crucial role in enabling this. Having a robust overview of relevant design roles and competencies is of foundational importance for the development of circular design tools and methods, and for the development of circular economy-based design curricula in higher education. However, how the role of design and the competencies required by designers need to change has hardly been investigated. Building on insights from literature regarding competencies of designers required to consider sustainability, sustainable design, and circular design, we developed a framework in which these competencies are related to the functional, coordinating, and strategic roles that have been recognized within the literature for designers. To complement the results from the literature with insights from practice, a single longitudinal in-depth case study was carried out describing a lease and refurbishment pilot conducted by a Dutch design-driven manufacturer of baby strollers. This case study allowed verification of the literature regarding the functional and coordinating roles of the designer. In addition, we were able to fill the gap observed in the literature regarding the strategic role product designers can assume when designing offers for circular business models. The competencies that we found are (1) the ability to concurrently develop the circular business model and the product's design and (2) the ability to anticipate how the circular offering will evolve over multiple lifecycles. These findings have been used to expand the framework.2 of 15 to give manufacturers control over their products over the life cycle and result in reliable product return rates. This would facilitate the recovery of the value embedded in products [4]. Hence, the shift from selling products to providing access-based payment models is considered an important business model for a circular economy. Product design then also includes the design of the associated service.Product design's role in shaping a circular economy is often described as pivotal. The Ellen MacArthur Foundation, for instance, states: "At its core, a circular economy aims to 'design out' waste. Waste does not exist-products are designed and optimised for a cycle of disassembly and reuse" [4] (p. 7). In a similar vein, Thomas argues "Design will play a key role in the transition to a circular economy" [5]. This sentiment is echoed by the European Commission, for instance, in their recent European Strategy for Plastics in a Circular Economy: " . . . where the design and production of plastics and plastic products fully respect reuse, repair and recycling needs and more sustainable materials are developed and promoted" [6] (p. 5).In spite of the widespread recognition of the importance of design in a circular economy, there is very little empirical research into the...

In a recent study, we identified seven key circular competencies for design: (1) Design for Multiple Use Cycles, (2) Design for Recovery, (3) Circular Impact Assessment, (4) Circular Business Models, (5) Circular User Engagement, (6) Circular Economy Collaboration, and (7) Circular Economy Communication. These were derived from small-scale studies with designers working in the Netherlands. We set out to assess to what extent this set of seven competencies is recognized by an international group of designers and to evaluate whether any competencies are missing. We used an online survey to collect data from 128 respondents from 25 countries working on circular economy projects. The survey results showed that respondents use and have expertise in all seven competencies and they stressed the practical importance of two new competencies: Circular Systems Thinking and Circular Materials and Manufacturing. The resulting set of nine key competencies is the first internationally verified, coherent set of key circular economy competencies for design. This set will strengthen the pedagogical base of design for a circular economy and will guide the development of circular design methodology.