Most respondents considered modifiability as relevant for addressing both technical and environmental sustainability. Functional correctness, availability, modifiability, interoperability and recoverability favor positively the endurability of software systems. This study has also identified security, satisfaction, and freedom from risk as very good contributors to social sustainability. Satisfaction was also considered by the respondents as a good contributor to economic sustainability. Background Since sustainability became a challenge in software engineering, researchers mainly from requirements engineering and software architecture communities have contributed to defining the basis of the notion of sustainability-aware software. Problem Despite these valuable efforts, the assessment and design based on the notion of sustainability as a software quality is still poorly understood. There is no consensus on which sustainability requirements should be considered. Aim and Method To fill this gap, a survey was designed with a double objective: i) determine to which extent quality requirements contribute to the sustainability of software-intensive systems; and ii) identify direct dependencies among the sustainability dimensions. The survey involved different target audiences (e.g. software architects, ICT practitioners with expertise in Sustainability). We evaluated the perceived importance/relevance of each sustainability dimension, and the perceived usefulness of exploiting a sustainability model in different software engineering activities. Results