This paper presents a part of work developed inside the ULCOS project, which aims at the radical reduction of CO2 emissions from iron and steel production, through new routes that must be sustainable, i.e. environmentally-friendly, economically viable and socially acceptable. In order to demonstrate their sustainability, Key Performance Indicators are the main tools developed inside the work package 9.4, “Sustainability Model & Process Selection Tool”, which aims at making complex issues more manageable. Key Performance Indicators (KPIs) are the most useful tools for evaluating and managing not only the environmental and economic impacts, but also the social impacts. The assessment of social aspect of sustainability must be taken into consideration, nevertheless the prediction of social impacts is often hard to be done, not only because of the lack of a clear cause-effect relationship but also because of the difficulty to analyse and to predict social phenomena, especially through a quantitative approach. The purpose of this work is to present a methodology, based on both quantitative and qualitative approaches, carried out in order to develop the social indicator (Local Community Impact Indicator), which has primarily taken into account possible impacts of a current integrated steelworks on the communities within the close vicinity of the plant operations.