SISSTEM “Sustainable Island Solutions through Science, Technology, Engineering and Mathematics” is a higher educational programme created in 2019 at the University of Aruba in response to the need for engineering education and research in Small Island Developing States (SIDS). In this contribution, the SISSTEM programme is introduced, and how SISSTEM equips engineering students with hard and soft skills while addressing local sustainability challenges is showcased through two case studies. The first case study presents a bachelor course that combines sustainability theory with a teamwork project in which students conduct an energy audit to a local institution. With this course, students acquire skills to support the energy transition in Aruba. The second case study focuses on the involvement of university students in the creation of a citizen science mobile phone app to tackle waste challenges. This case study presents how students can become agents of change to contribute solving waste management challenges on the island. Overall, these two case studies showcase how by combining theory and project-based education, students learn to integrate STEM knowledge into multidisciplinary solutions to complex sustainability challenges. In fact, given the cross-cutting nature of sustainability transitions, educating students in integrating the natural environment, technical, social, and economic aspects in engineering solutions is key to increase resilience of islands. As such, at SISSTEM, students acquire hard skills related to their engineering specialisation, as well as soft skills such as integration of disciplines, contextualization, and collaboration.