Joltin' Joe.

I always found it amusing that New York Yankee slugger Joe DiMaggio--"Joltin' Joe," as the sportscasters dubbed him--went on after retirement to stump for kitchen coffee makers. But one thing Mr. Coffee never jolted us with were the real facts about America's favorite hot beverage.

As you'll read in our revealing cover story this issue, coffee is second only to oil in terms of dollars traded worldwide, yet the smiling faces on the packaging give no hint that the popular drink is linked to a host of social and environmental ills. These include widespread deforestation, loss of biodiversity, and substantial impact on the lives of indigenous people who make up a large part of the world's 25 million small-scale coffee farmers. They have an extremely hard time earning a decent income because of painfully low prices for their crops. And their lands are often destroyed by chemical-intensive, large-scale industrial coffee plantations that use enormous amounts of water and produce toxic runoff that poisons the fish and streams they rely on.

However, as you'll also read in this issue, some impressive efforts by organizations like Rainforest Alliance, Conservation International and others are underway to improve coffee's social and ecological footprint. And consumers can do their part by seeking out coffee labeled "Fair Trade," "bird-friendly," "organic" or "shade-grown" to help ensure that their dollars are heading the industry in the right direction.

The struggle to make coffee more sustainable is a great issue for greens to rally behind. It gives us the opportunity to demonstrate, using a common household foodstuff; the very meaning of sustainability. It's not enough, for example, that coffee is affordable for just about anyone, and that it tastes good and gives many of us that "start" we need before we head off to work. It needs to live up to more rigorous standards.

Any human enterprise should produce something useful for society while also benefiting those who make it. Both sides of the equation need to profit: The product itself should be safe and healthy for the user; and the process of making it should be safe for the maker. The product should be affordable for those who need it, and should also allow the maker to earn a decent living. And those on the sidelines--be they other people, other cultures or other species--should also benefit, or at least not come to harm. Further, the environment on which the product's longevity depends should not be so despoiled that it one day might no longer be able to produce.

As I see it, all of these conditions taken together are much like the spokes in a bicycle wheel. If one or more of the spokes are weak the whole system is weak. If many are weak, the system collapses. This metaphor applies in many instances. Take global warming: It's wonderful that human beings have the ability to engineer so many incredible innovations, from automobiles to cruise ships the size of small towns to buildings that nearly touch the sky. But the system is weak if the price we must pay is a despoiled ocean environment, skyrocketing asthma rates or a warming planet. Indeed, Hurricane Katrina, whose ferocity was likely increased by the warmer ocean temperatures brought on by global warming, maybe an indicator that the system is near collapse.