Human movement through cities is largely constrained to pre-designed spatial networks that embody values of power, aesthetics, and prevailing technology. The quality of urban spaces – and for whom these spaces perform – rests upon these outcomes of urban design and architecture. Although circulation networks critically underlie city mobility and human dynamics, it can be difficult to acquire and consistently analyze high-quality network data. This talk presents new urban data science methods to explore city spatial structure and circulation worldwide – including in developing countries. It considers how to understand urban equity, resilience, accessibility, and human mobility using open-source software and collaboratively-generated, free data. Finally, it introduces several tools and methods to understand, visualize, re-think, and communicate complicated urban patterns and spatial outcomes.