Supporting sustainability has recently become a much discussed research topic and the RE4SuSy workshop series has established a strong and growing research community around the different aspects of sustainability. Software is increasingly the driver for change in business and social spheres of life: it changes life styles and business practices. Since requirements define how and what the software will do, we maintain that requirements engineering is the key point in software engineering through which sustainability can be fostered. The International Workshops on Requirements Engineering for Sustainable Systems (RE4SuSy) is concerned with research on techniques, tools, and processes for sustainability through requirements engineering. RE4SuSy is an interactive workshop: the contributors and prospective participants will engage well before the workshop date through online collaborative writing, discussion, and peer feedback. The workshop aims to foster community growth by supporting new collaborations, holding preliminary case studies, discussions, and continuous birds-of-a-feather group work.

Software is a main driver for change in business and society, in changing life styles as well as business practices. Since requirements are the starting point for defining software, requirements engineering is the key point in software engineering through which sustainability can be fostered. Presently, researchers are exploring the concept of "sustainability requirements", and how to support the elicitation, documentation, and conflict resolution of such requirements. It has been shown that requirements engineering has indeed an important role to play to ensure that future socio-technical systems are sustainable. For example, requirements can impact on the style and quality of services to be delivered, along with the hardware needed to deliver them; the scale and pattern of software and systems electricity consumption; the potential premature obsolescence of hardware, etc. Further, as ubiquitous socio- technical systems alter the way we live, the requirements of those systems have to be carefully written such that those new ways of living are more sustainable. In industry, companies not only want to be "ecologically trendy", but also become aware that sustainability requirements have strategic impacts on business organization and value creation, as with zero paper projects that revolutionize enterprise architectures, or intelligent power grids that lead to delivering innovative services. This workshop aims to provide an interactive stage for researchers and practitioners to share and exchange their latest work, to collaboratively work on expanding the body of knowledge in RE for sustainable systems, and to jumpstart new collaborations through the live creation of teams that commit to work together on concrete topics and in-workshop case studies and experiments.