We know what needs to be done to live more lightly on the land.

Plenty of awareness campaigns detail the merits of sustainable-living commitments, ranging from recycling to water conservation. Environmental educators "use radio, television news-print and the Internet to push information to people, with the hope that it will change behavior," says Doug McKenzie-Mohr, an environmental psychologist.

The trouble is, McKenzie-Mohr argues, this strategy doesn't work.

"When it does, it's in a very marginal way," said the author of "Fostering Sustainable Behavior: An Introduction to Community-Based Social Marketing."

McKenzie-Mohr says people are seldom motivated to action when simply presented information — that it is more effective, as marketers have learned in free-enterprise America, to encourage, ask for commitment, and provide incentives to act. On Monday, he'll give a lecture and lead a workshop tailored for green leaders who are trying to persuade us to ditch our wasteful ways.

McKenzie-Mohr proposes a series of steps to motivate people to follow through on green initiatives, including these:

• Study potential target behaviors. For example: Before the City & County of Honolulu asked people to recycle their cans, bottles and newspapers at curbside, officials sought public input through surveys and community meetings.

• Strategize how to knock down obstacles that stand in the way of the desired action. It can also be helpful to put up "barriers" that discourage wasteful habits. In the case of recycling, when the city scaled back garbage pickup to once weekly, it encouraged people to put mixed recyclables and green waste in the right bins — because space would run out in the garbage cart.

After working with Mc-Kenzie-Mohr a few years ago, Honolulu's recycling coordinator Suzanne Jones applied some principles of community-based social marketing to the curbside recycling program, which is expanding this spring to include 160,000 O'ahu homes.

The city toppled a "convenience barrier" by providing households with a blue cart for mixed recyclables, a green one for green waste and calendar-reminder stick-ers, Jones said.

Collective peer pressure also comes into play, said McKenzie-Mohr, who lives in Canada and presents 40 to 50 workshops a year aimed at implementing and expanding sustainability efforts.

"The mere act" of rolling out a cart "showcases that curbside recycling is important," he said. "The behavior matters because you can see the engagement that other people have in it."

Noting that visibility gives curbside recycling a popularity edge over backyard composting, McKenzie-Mohr suggested that households now quietly turning organic kitchen waste into richer soil for gardens and landscaping could nudge neighbors to follow suit by slapping a sticker on their recycling carts reading: "We compost, too."