Encountering the title of this book by Richard Forman, my first reaction was one of surprise. It is commonplace, of course, that cities are embedded in natural systems, but the modern city seems such a triumph of modern technology over the constraints of nature that one can easily understand why urban planners have rarely found it necessary to spend much time talking with urban ecologists – or, to state it another way, why ecology and urban planning have remained quite separate domains of inquiry and action in the modern division of labor.

Ecology, a branch of biological sciences, strives to understand relationships of interdependence in the natural world, and (while not at heart activist) at times to devise strategies for their preservation. As such, of course, it informs environmental regulators and thereby places some constraints on development activity. Urban planning, on the other hand, exists to provide analysis in the service of action, and its principal concerns historically have been economic – to pursue and facilitate development while striving as well to preserve and enhance the market value of existing property investments. Planners have other concerns as well, to be sure, such as improved public health, social equity, and an attractive public realm – all of which have vital ecological dimensions. So one would be hard-pressed indeed to find a planner who disagreed with the proposition that good plans must be ecologically sound.