We report on the development of a holistic framework to organize and integrate quantitative information characterizing the performance of Urban Waste Management Systems (UWMS) across dimensions and scales. The framework builds on the theory of metabolic networks and the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) accounting method. We perceive the UWMS as an organ of a socio-ecological system that modulates the interaction between the metabolic processes of the urban area and those of the embedding ecosystems providing inputs and local sink capacity. Building on these premises, we can define: (i) the flow of wastes produced by the urban system in quantity and quality; (ii) the mix of inputs required for the operation of the different stages of the waste management process, such as technology, labor, energy, water and material flows; (iii) the degree of openness of the system, that is, the imports and exports of urban waste flows in the different stages of its operation; (iv) the final outputs released into the local environment. The proposed framework can accommodate various indicators referring to the socio-economic performance of the UWMS (viability and desirability) and those related to environmental impact/stress (feasibility). Theoretical considerations are illustrated with preliminary data from a case study on the Metropolitan Area of Naples, Italy.