Newsweek published its first annual Green Rankings in September, a list of the S&P 500 companies ranked and scored by the magazine for their environmental impact and reputation.

The list, which reportedly took 18 months to compile, was created with the help of environmental research groups, including KLD Research & Analytics, Trucost and CorporateRegister.com.

The top 5 Companies on the Green Rankings are:

1. Hewlett-Packard
2. Dell
3. Johnson & Johnson
4. Intel
5. IBM