Looking for a way to help the planet, but not sure where to start? Look no further than your purse. Think about it: Women are the most powerful consumer force in the world, and if they collectively started using their economic clout to buy green, they could force manufacturers to listen up and take notice. Pretty empowering, huh? The challenge is knowing when to spend your money—and when to keep it in your purse. These seven simple principles will help you make sure your dollar has the greatest green impact.

NEXT: Buy less >>

Excerpted from:

Big Green Purse by Diane MacEachern, © 2008 Penguin Group.