Discovering Sustainability Requirements: An Experience Report Martin Mahaux, Patrick Heymans, and Germain Saval PReCISE Research Centre University of Namur, Belgium {martin.mahaux, patrick.heymans, germain.saval}@fundp.ac.be Abstract. Sustainability has become one of the “grand challenges” of our civ- ilization. Because of their pervasiveness, the way we design, and consequently use, software-intensive systems has a significant impact on sustainability. This gives software requirements engineering an important role to play with respect to society. However, there is currently no specific support for handling sustainability requirements, while such support exists and has proved useful for other quality requirements like security or usability. This paper reports on a software project in which sustainability requirements were treated as first class quality requirements, and as such systematically elicited, analysed and documented. The authors in- tended to assess how current techniques support these activities. Beyond raising awareness on the importance of sustainability concerns in requirements engineer- ing, this experience report suggests that, while a lot of work remains to be done, small and easy steps may already lead us to more sustainable systems. It also contributes to the agenda for the requirements engineering researchers concerned with sustainability. 1 Introduction Achieving sustainability is recognized by many as one of the “grand challenges” of our society. Although there is a lot of debate surrounding this endeavour (e.g., as to its justifications, the means to achieve it, etc.), we leave the controversy aside from this article. He, we take the pragmatic stance of adhering to one of the common definitions of sustainable development. The United Nations’ Brundtland commission defines sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [12]. It is traditionally considered that sustainable development involves three major “pillars”: social, environmental and eco- nomic sustainability. In this paper, we only focus on environmental sustainability. We also adhere to the common thesis that environmental sustainability (simply called sus- tainability henceforth) is threatened by a number of practices such as depletion of non- renewable resources, production of non-recyclable or toxic substances, etc. Over the last decades, information technology (IT) has become one of the leading industries worldwide. Its effects on the environment are considerable. Its most obvious