This paper contributes by clearly identifying the shortcoming of design thinking as well as pinpointing where to begin in terms of achieving a more solid conceptualization of the concept. To identify its potential shortcomings, this study examines the theoretical structure of design thinking and compares it to the theoretical structure of designerly thinking. This comparison suggests that the current conceptualization of design thinking lacks methodological approaches, that is, guidelines concerning how best to approach a given problem and how to competently select, configure, apply and evaluate the tools and techniques needed to tackle that problem. In its present form, design thinking facilitates the general, non-situated application of tools and techniques, which is neither linked to nor anchored in a design paradigm.

Product longevity is a key to improving the sustainability of production and consumption patterns. However, at many companies, extending product longevity requires overcoming several complex barriers. Identifying how to begin this process can be difficult; moreover, the available solutions may seem too complex or radical and, therefore, may be ignored as viable options. The purpose of this paper is to study the approaches and decision patterns that enable best-practice companies to produce high-longevity products. We aim to map approaches to implementing product longevity through a multiple-case study of 18 best-practice companies that systematically work to ensure product longevity. Through interviews with developers, CFOs and CEOs at companies that strive to design and produce long-lasting products, we identify three key types of approaches to implementing product longevity: performance-driven, behavioural change-driven and vision-driven approaches. This study reveals several types of approaches to implementing product longevity successfully. This contribution advances our understanding of how companies can engage with and foster product longevity at different stages of the development process.

Product life extension is recognized as an important tool for creating more sustainable production and consumption patterns; yet, there is a lack of studies with comprehensive insights into how consumers interact with products throughout the product’s life span, or knowledge about the strategies consumers apply to change their behaviors and avoid premature disposal. The purpose of this study is to explore the motives and strategies users apply that positively affect product lifetimes, which provides much-needed input on the consumer’s perspective in the circular economy. The study applies a qualitative ethnographic research methodology on 26 households, in which we investigated how differently motivated users engaged with products in their homes; how they approached, developed, and modified products to fit personal needs, and, eventually, end up prolonging product lifetimes. The study contributes a new perspective on user research in the circular economy and suggests a new paradigm for circular conceptual design. Specifically, the study shows how existing user strategies for product longevity can be identified and used as a starting point for designing products and services that prolong product lifetimes.

Companies are pivotal in transitioning from a linear economy to a sufficiency-based circular economy. However, circular research lacks the necessary tools and processes to engage companies, customers, and downstream suppliers in preserving the value of their products post-launch. Effective value preservation requires close collaboration among producing companies and their ecosystem stakeholders to identify when value is decreased or destroyed over the product’s lifetime and to develop shared strategies to preserve or increase this value. This paper contributes to the development and empirical evaluation of the Circular Value toolkit. Based on demonstration with 15 SMEs and 24 PhD students, we found that the Circular Value toolkit supports companies in 1) identifying the points in the product lifetime where value is currently decreased or destroyed; 2) developing ideas and concepts to prevent value destruction; and 3) identifying barriers and opportunities for initiating collaboration with ecosystem stakeholders to ensure the efficient preservation of product value throughout the product’s lifetime. A valuable next step will be to validate the toolkit’s long‑term effects and examine its implementation within large organisations.