This paper aims to highlight the main criteria for metropolitan efficiency assessment. After the institution of the Metropolitan Cities in Italy that give them the power of territorial metropolitan planning, an important issue is about what knowledge is required. We want highlight strengths and weaknesses of each criteria in reference to metropolitan level, with the aim to have better grounded knowledge framework, outlining environmental and functional points of view.
Keywords: Ecological footprint; greenhouse gas emissions; ecosystem services; sustainable mobility; public open spaces.