Hanoi combines some of the world's highest human densities with scarce public spaces. Green spaces are very limited too, even by the standards of Asian Cities. Providing public spaces where youths can flourish is a tall order for the Vietnamese capital. Bringing together Canadian and Vietnamese researchers and the NGO HealthBridge, this 2 year research project tackled the issue of youths and public space in Hanoi with the hope of contributing to the positive engagement of young Hanoians with the city where they live. With a data-visualization website, we aimed to provide a picture of the evolution of public spaces in the region (in terms of overall spatial distribution, available areas, quality, and usage) and an understanding of the driving forces behind these changes. **(I personally submit to the "Visualizing Cities" as a researcher in the project, but mostly as the designer of the www.hanoiyouthpublicspace.com website, and all its data-visualization content (maps, graphics, data, etc.). I therefore don't submit any attached files, as the final product is mostly HTML content).