Environmental design, urban climate and user experience are mutually interdependent. This paper understands the urban heat-island phenomenon as the core notion, and both quality of life and environment are implicated. Urban geometry and fabric appear to be climate-interactive - from grid form and building massing to thermal mass; so too are thermal sinks, and lifestyle sources...hot cars and roads, eg. >From the experiential point of view, warmer urban climates have discernible impacts: avoidance behaviour of inclement places depresses street-life dynamic, and sense of security; while heat-stress adaptation is a major health risk, and temperature influences photochemical smog intensity. Cities interact with their climates, citizens with their city.