Increasing the use of social sustainability in the decision-making process for building and infrastructure projects requires that it be defined such that it can be evaluated objectively. One potential indicator of social sustainability in infrastructure projects is public opinion, which can provide a means to evaluate the level of social sustainability on a project based on personal values. Public opinion includes both support and opposition for a project. In this study, the causes or triggers for public opposition to a construction project are identified and then compared to principles of social sustainability to determine if they are related. Eight case study projects were used to identify common triggers of public opposition. The results suggest that common triggers of public opposition are related to land acquisition, escalating construction costs and the presence of endangered species on the project site. Eight of the twelve principles of social sustainability that were identified were determined to be related to public opposition. The results of this study suggest that public opposition could be used as a measure for some elements of social sustainability but that further research into other measures for social sustainability is necessary.