Greening a college campus is not a one-size-fits-all proposition. In Yale's custodial services and procurement departments, two different approaches are on display. Call it culture vs. systems, or "teach a man to fish" vs. "lead a horse to water."

On the custodial side, Bob Young is applying the scientific method. "We're establishing a culture of investigating being green," Young says. "Early on, there was a big push from the administration: 'These are the products we should buy.' I resisted that, because my supervisors" -- who report to Young and oversee the Yale custodians -- "should know why we're buying these products. I wanted this to be an ongoing investigation."

Custodial services uses only recycled paper products.

This learn-it-from-the-bottom-up approach takes time. "It took pretty much all of last year to do the tests and decide on what products to use, what products to eliminate," Young says. None of the green floor finishes that Young's crews tested made the cut. They simply weren't durable enough. Nor has the department found a non-toxic disinfectant. They're adapting to a non-ammoniated glass cleaner: it's non-toxic, but it doesn't evaporate quickly, so "you have to rub twice as much."

Young is happy with the results of the year of testing. Since the summer of 2006, custodial services has used only recycled paper products. More recently, the custodians have adopted the non-ammoniated glass cleaner -- as well as a general cleaner that contains hydrogen peroxide, rather than solvents. They're also testing a mop that has a built-in supply of cleaning fluid, so it uses less water.

 "You can have green products, but they will sit on the shelf if people don't use them," says Young. "You've got to have a green culture."

Brenda Naegel has a different challenge. The procurement department's lead person on green purchasing campus-wide, she has been looking at these issues for five years. Nevertheless, "we haven't made the strides that we would like to see," she says.

Brenda Naegel in procurement has a simple strategy: make it easy.

"But we are going to move forward," Naegel promises. The biggest push at the moment is copy and printer paper. "We asked the [Yale] community, for the last several years, to use paper with 30 percent post-consumer recycled content," she says. "Unfortunately, only about 55 percent" do so. Only 1 percent use paper made entirely from post-consumer content. The goal is to turn that 1 percent into 100 percent by the end of 2008.

Naegel has a simple strategy: make it easy. In effect, make it the default, so that people have to choose not to buy recycled paper.

Cost is key. Her department recently negotiated a price cut, making 30 percent recycled paper slightly cheaper than virgin stock. (The 100 percent recycled has also come down in price, but it still costs "significantly more.") Convenience is also crucial. On Yale's electronic procurement system, Naegel has arranged to put recycled paper "front and center."

More broadly, Naegel is undertaking a green investigation similar to the custodians' for products and services that Yale buys in large volumes. Naegel says that suppliers vary in their response to Yale's inquiries. "Some of them are like, 'We've got it covered. When can we come in and do a lunch-and-learn and bring in the cupcakes with the green icing?' Some just don't respond. Then there are those [who say], 'You're killing me. But I'm going to do it, because my other customers are going to ask me for the same thing.'"