With more than 40 areas of specialization and a combined 100+ years of experience in their fields, CSG consultants have the know-how, expertise and understanding to help with any sustainability projects, no matter how large or small.


Areas of Expertise:

Sustainable seafood

Restaurant development, especially sushi

Whaling issues

Fishery and aquaculture assessment

Media and press development





CassonTrenor, Consultant,
Coldstream Sustainability Group

MA in International Environmental Policy from the Monterey Institute of International Studies; B.A. in Political Science from Hobart College.


From saving the whales of the Antarctic to studying the salmon of Alaska, Casson Trenor has worked to support stewardship of marine resources in all five oceans and countless seas. Casson worked for the sustainable seafood organization Fishwise in Santa Cruz before taking his current position as Senior Markets Campaigner with Greenpeace USA, where he spearheads the organization’s efforts to hold restaurants and supermarkets accountable for their seafood sustainability practices as well as educating the public about the global fisheries crisis. Trenor has been involved in affecting major change towards sustainability in the seafood operations of many different companies, from small operations to international conglomerates. Trenor is a frequent commentator on sustainable seafood issues and has appeared in regional and national publications, including NPR, New York Times, Boston Globe, Christian Science Monitor, San Francisco Chronicle, Los Angeles Times, Seattle Times, Tampa Tribune, the UTNE Reader, Hemispheres, Tokyo Weekender, and Edible San Francisco. He is the author of Sustainable Sushi: A Guide to Saving the Oceans One Bite at a Time, owns and maintains www.sustainablesushi.net, and is a founder of the world’s first sustainable sushi restaurant, Tataki Sushi and Sake Bar in San Francisco and has also converted two “conventional” sushi bars, Seattle’s Mashiko and New Haven Connecticut’s Miya’s, into sustainable sushi operations. In 2009, Trenor was named a “Hero of the Environment” by TIME Magazine.