Product development companies’ attention and desire to contribute to sustainable development is growing fast but requires new capabilities. The socioecological systems constitute a complex landscape of operating conditions from which product development identify needs for new products. Correct needs interpretation is essential to ensure that the requirements that the needs are transformed into do represent the shared understanding of the design problem that is to be solved. However, companies find it challenging to integrate sustainability into requirements. Socioecological criteria therefore tend to be down prioritized in trade-offs with traditionally identified requirements for engineering design.

This thesis asks the following question: “In which ways can decision-making practices for requirements development and management support sustainable product development?” and aims to provide deeper knowledge to academia and support product development companies that wish to advance their contribution to sustainable development. A mainly qualitative research design using exploratory, descriptive, and prescriptive studies clarifies the research gap, and proposes and evaluates novel approaches to improve the state of knowledge and practice. These research studies are represented by the seven publications within this thesis. The first was a systematic literature review on current methods and tools for sustainability integration into requirements. Thereafter followed a multiple-case study with semi-structured interviews at seven Swedish product development companies. A model of five key elements of sustainability integration in requirements was proposed, which in a third, focus group case study with four companies, was developed into, and tested as, a self-assessment tool. The results were discussed in relation to theory on requirements engineering and sustainability design criteria, which emphasized that companies lack capabilities to contextualize requirements development using wider sustainability- and systems perspectives. Decision-makers responsible for requirements weighting need to anchor sustainability as a value driver which requires transparency and traceability in decision-support. A fourth study therefore explored sustainability integration in value modelling for concept selection, and a fifth study proposed an approach to guide sustainability criteria development following requirement characteristics. The sixth study proposed an approach to inform requirement analysis through improved systems contextualization, transparency, and shared understanding of sustainability in relation to other design objectives. Finally, the seventh study provided an outlook and initial discussion to guide the identification of value drivers on a macro-level in society which could leverage an increased uptake of sustainability-oriented requirements in product development

Altogether this thesis provides insights and approaches to guide companies to advance towards sustainable product development through the lens of requirements. Examples include key characteristics of, and principles for, identifying sustainability criteria and developing requirements using strategic sustainability thinking, as well as a support tool for guiding activities in different steps of the requirements development. The findings can also be used in education of future engineers and decision-makers, and for continued research.