ESG ratings describe companies' environmental, social and governance performance. This link explains with more detail what these are, why they are useful, and where to find them.
CorpWatch maintains Gulliver, a database of what the organization describes as "corporate crimes"--ethical, moral, or legal violations by corporations.
Companies use SASB standards to report their sustainability efforts to their investors. This list provides examples of how companies have created documents that assess and share their own efforts towards sustainability via the standards.