U4SSCThis publication has been developed within the framework of the United for Smart Sustainable Cities (U4SSC) initiative. It provides cities with a methodology on how to collect data or information from key performance indicators (KPIs) for smart sustainable cities (SSC). This set of KPIs for SSC were developed to establish the criteria to evaluate ICT's contributions in making cities smarter and more sustainable, and to provide cities with the means for self-assessments.