This week, a new study by Toronto-based media and research group Corporate Knights revealed that adidas and H&M are among the world's most sustainable companies. As reported by Fashionista, Corporate Knights' 2016 Global 100 Most Sustainable Corporations in the World Index measures the sustainability of publicly traded companies with a market capitalization of at least $2 billion as of Oct. 1, 2015.

Each company was evaluated using 12 different "key performance indicators," or KPIs, that include criteria such as energy productivity, water productivity, employee turnover, and leadership diversity. While not all of these factors directly measure how eco-friendly these companies are, they are meant to measure the companies' overall sustainability, or in other words, their ability to maintain their operations running.

Adidas dropped two spots on the list from last year, coming in at number five with an overall score of 73.1 percent. We've already seen adidas introduce a few new efforts to create more sustainable products, especially in regards to footwear.

H&M came in at number 20 with an overall score of 68.3 percent, after implementing a few different initiatives to produce more sustainable goods over the past couple of years. The company has been offering a 15 percent discount to customers who bring in recycled clothing to drop off centers inside their various retail locations, and also released denim lines made with fabrics from recycled clothing.

It's interesting to note that these two brands' closest competitors, Nike and Zara respectively, did not make the list.

One other notable fashion company on the list is Kering, the French holding company that owns Alexander McQueen, Balenciaga, Gucci, Puma, Saint Laurent Paris, and a few other big brands. Kering came in at number 43, with an overall score of 63.7 percent.

In terms of fashion and apparel companies, these three are the only ones to make the cut. Take a look at the rest of the list here, to see what other types of companies made Corporate Knights' list.