I've seen enough research data on Americans' green buying habits over nearly twenty years that I've become immune to much of it. It's not that I think such research is shoddy; it's just that I've found consumers' credibility on the issue wanting, as I've noted in several . . . previous . . . posts.

Consider: A 1989 survey by the Michael Peters Group, a now-defunct consulting firm based in New York and London, found 89% of Americans saying they were concerned about the environmental impact of the products they purchased; fully 78% said they were willing to pay as much as 5% more for a product packaged with recyclable or biodegradable materials.

Of course, we know well that only a fraction of Americans buy green products -- or, at least, buy more than a few such products on a regular basis.

(I'm leaving organic and other food items out of this equation for the moment. While much of these purchases certainly qualify as "green," the motivations behind them have more to do with personal health and well-being than with planetary considerations.)

In the eighteen years since Michael Peters, a succession of surveys have yielded similar stats, numbers that show up frequently in conference presentations and business plans. After all, if you were selling a product or service aimed at a green-minded audience and wanted to convince investors, business partners, and others that your greener mousetrap had a robust market, wouldn't you want to invoke such optimistic-sounding data from venerable research firms? I would.

Given this context, I couldn't help but note a press release last month stating that the "vast majority" -- 87% -- of American consumers say they are "seriously concerned about the environment." Moreover, said the release:

A vast majority of consumers say a company's environmental practices are important in making key decisions including: the products they purchase (79%), the products/services they recommend to others (77%), where they shop (74%), where they choose to work (73%), and where they invest their money (72%).

These findings came from the 2007 GfK Roper Green Gauge, the latest edition of an (almost) annual survey of Americans' green-shopping attitudes that began in 1990. As I've noted previously, each year Green Gauge tracks the environmental attitudes and belief systems of five market segmentations of American consumers. I've been watching Green Gauge results since they began and find them an interesting, and sobering, look at Americans' green Zeitgeist.

Given Roper's findings -- nearly nine in ten Americans say they are fretting over the fate of the earth! -- I wanted to learn more. A recent conversation with Katherine Sheehan, senior vice president at GfK Roper Consulting, helped me get to the bottom of it all.

For starters, that 87% figure turns out to be misleading -- the overly enthusiastic hyperbole of a press release writer, I'm guessing. Turns out that only 41% of Americans say that their concern for the environment is "very serious and should be a priority for everyone." Another 41% said that their concern about the environment is "somewhat serious, but there are other more important issues that we need to address."

Add those up and you get the 87% who are "seriously concerned about the environment," as the press release put it. "I think that's a little bit misleading," concedes Sheehan.

Enough about that. Other parts of Green Gauge were more enlightening. For example: Company websites, brochures, and annual reports are the last place consumers look to for information on company environmental practices, Roper found. The biggest sources of information are traditional media and word of mouth: TV programs (59%), newspaper articles (49%), online articles (39%), and friends, family, and "other people you know" (34%). Environmental organizations ranked sixth (25%), blogs eighth (18%), followed by government agencies, business magazines, community groups, and -- finally -- corporate communications.

The one exception are product labels, which seem to have a fairly high level of credibility. "We see that people tend to really believe product labels and product labeling," says Sheehan. "So, if something says it's biodegradable, the consumer has a level of trust with that communication."

Still, it's evident that companies have a lot of work to do to gain cred among consumers when it comes to the environment. Some of that likely has to do with the impenetrable nature of most company websites and annual reports, and the feel-good nature of much of their other environmental communications. Even the most committed consumers would have problems wading through some companies' output, let alone assessing what it all really means.

As a rule, green products still seem an afterthought for most consumers. Roper found that 28% percent of consumers have purchased a product in the past two months "because the advertising or label said the product was environmentally safe or biodegradable." (That seems to counter Roper's finding that nearly eight in ten consumers think that companies' environmental practices are important in the products they purchase.)

So, what's keeping consumers from doing more? Greener products are "too expensive," say 74% of consumers, while 61% say they don't work as well. Fifty-five percent believe that "many 'environmentally safe' products are not better for the environment." (So much for believing product labels.)

Such findings worry me. They sound much like consumer responses did a decade or more ago. True, some things have changed in that time: the aforementioned growth of organic, natural, and locally sourced foods; the availability of renewable power and green energy from local utilities; the advent of hybrid-electric vehicles; and the growth of energy-efficient technologies in many consumer products, including computer equipment. And then there's the rise of retailers -- Wal-Mart, Home Depot, and others -- that are making some greener products more affordable and available to the masses.

But the pace of change seems unbearably slow, and incremental, and not widespread. And despite the optimistic findings of Roper and other firms sussing out Americans' green buying habits, I'm discouraged and impatient. What will it take for a critical mass of competitively priced, widely distributed, and high-quality green products to be available -- enough so that buying them feels the rule, not the exception? What will it take for green to finally be mainstream?