'Tis the season, or so the media would have us believe, to be green. Al Gore is preaching the gospel of sustainability in multiplexes across the country. Elle and Vanity Fair magazines published dueling green issues this spring. And tonight, a six-part series on sustainable architecture and design � it's officially called "Design e2: The Economies of Being Environmentally Conscious" � begins on PBS.

The series is narrated by Brad Pitt, a well-known architecture buff and, as you may have heard, father of a week-old baby girl. (Those two facts are not unrelated, as it turns out: The kid's middle name is Nouvel, presumably in honor of the painfully hip French architect Jean Nouvel.) If it has certain blind spots, particularly what sports fans call East Coast bias, it's also an engaging overview of the most prominent players, recent breakthroughs and stiffest challenges in sustainable architecture. And it's produced with enough panache — particularly in the brooding camera work by Robert Humphreys, which owes something to trendy architectural photographs by Olivo Barbieri — to make its more medicinal lessons go down quite easily indeed.

Pitt starts each episode with a rhetorical introduction: "They use 40% of the world's energy and emit 50% of its greenhouse gases. They are not the cars we drive. They are the buildings we work, live and grow in." Those statistics aren't new, but they don't seem to have completely sunk in yet, particularly with the environmental activists who continue to make the SUV the bête noire of the green movement.

Tonight's installment, on New York City, is essentially a made-for-public-TV version of an article by David Owen that appeared in the New Yorker magazine last year. Owen made the counterintuitive case that New York is the greenest city in America, simply because it's the densest — because its residents are more likely than those of any other city to use public transportation and to live in apartment buildings that share heating and cooling and water systems. He describes New York as a "community of consumption," and he means that in a good way.