As global resources deplete, there has emerged a need for designers to emphasize sustainability in engineering design. Towards this end, several researchers have presented design tools to support sustainable design; however, designers must be encouraged to adopt a sustainable design mindset and actively utilize these design tools and techniques in the design process. Prior research has identified the need for interpersonal skills such as empathy among individuals to encourage an active sustainable mindset among them. While several researchers have demonstrated the relationship between designers’ empathy and their identification of problem requirements in engineering design, little research has explored this relationship in the context of sustainable design. This direction of research is particularly important as environment-focused decisions in engineering design do not always benefit the primary user of a solution, but often affect secondary and tertiary stakeholders. Our aim in this paper is to explore this research gap through an experimental study with undergraduate engineering students. Specifically, we compared the relationship between participants’ trait empathy and their attitudes towards sustainability, in the context of environmental sustainability. We then investigated the relationship between their trait empathy, attitudes towards sustainability, and their identification of problem requirements in a design task. From the results, we see that students’ intentions towards sustainable actions positively correlated with their identification of environment-focused requirements. On the other hand, students’ perspective-taking — a component of their trait empathy — positively correlated with their identification of user-focused requirements. These findings provide an important first step towards understanding the relationship between designers’ individual differences and their adoption of sustainability in engineering design.