Defined here as the introduction or conservation of outdoor vegetation in cities, urban greening has bloomedduring periods of intensive urbanization. This was true in the nineteenth century and it seems to be the caseagain today, as a range of greening practices is co-arising during a third, and perhaps final, period of globalurbanization. Human health has been a recurring theme underlying the enduring aspiration to integrate naturewith city. Using change over time as a conceptual frame, this paper offers a comparative assessment of municipalgreening in the nineteenth and early twenty-first centuries, focusing on the potential implications upon, and therelationship between, such activity, urban design, and public health. In so doing, the na...