It’s true that global agreements, national cap and trade plans, and sustainable community strategies are desperately needed if we are going to slow or halt climate change. It’s also true that, especially as citizens of rich democracies, we should be pushing our elected leaders to take real action on this issue. In the meantime, however, if we all start making choices and changing our habits to become more aware of our resource consumption on the personal and household level, we can make a difference. This difference doesn’t lie in the one less trip we make in the car this week, or the few gallons of water we save by running only full loads in the dishwasher. The secret is in the aggregation of these changes, the things we do as individuals that add up to a change in group behavior. And as we know from the emerging science of social contagion, it’s possible that a lifestyle change you make could influence 1,000 of your closest friends.