The year 2017 was an important one for leggings: According to U.S. Census Bureau data, it was the first time imports of elastic knit pants surpassed imports of denim—a sure sign that the age of stretch has truly arrived. Now, with yoga pants in a rainbow of hues clogging every fast-fashion outlet, all that's left is picking the right pair. If you're working on going green, try Girlfriend Collective, a company pioneering the same eco-consciousness that has led restaurants around the world to abandon plastic straws. Girlfriend's two lines of leggings both sport fibers made from what would have otherwise been trash. Each pair in the Compressive line is woven using 25 plastic water bottles, preventing 18.61 pounds of CO2 from entering the atmosphere and saving 3.11 gallons of water. The leggings in the LITE line are made with recycled fishing nets, conserving 6.5 ounces of oil, preventing 1.85 pounds of CO2 emissions and saving 3.86 kilowatts of electricity. Plus, a portion of LITE sales go to the ocean cleanup group Healthy Seas, and both lines come in a range of jewel-bright colors—all for $68-$78, a price just about identical to Victoria's Secret.