Assessing contemporary society´s burden on the planet has been an ongoing project of many research teams in many disciplines. The recent emergence and proliferation of efforts to understand the role that cities play has led to the near-simultaneous development of various frameworks, methodologies and working models that capture urban resource flows and account for expenditures by industry, households and infrastructure networks; including power, water, and transportation. This paper introduces an urban resource flow model and describes the organization of its various elements with respect to two key fields; urban economics and ecology. The central organizing principle of this framework is the delineation of three fundamental urban activities occurring within a context of socioeconomic and biogeochemical material and energy transfers. These three urban activities are the direct link to key theoretical elements of both urban economics and ecology and thus facilitate a cooperative relationship between the evolving understanding of urban resource flows and economic and ecological urban thinking.