An interesting summary by WIPO as part of its celebration of World IP Day and this year's theme "Innovate for a Greener Future", highlighting the importance in particular of certification and collective marks in setting the standards for eco-friendly and sustainable brands.
Trademarks play an important part in ensuring that consumers know what they are getting, or that the product that they are buying complies with certain standards.
https://www.wipo.int/ip-outreach/en/ipday/2020/articles/sustainable_trademark.html