What Color is the Triple Bottom Line?

I recently posted a query on Twitter and Facebook asking a simple but vexing question: "Someone committed to the environment is called an environmentalist. What do you call someone committed to sustainability?"

The answers I got were largely snarky, smug, and, ultimately, unsatisfactory. (I probably should have added a single-worded addendum: "Seriously.") Suggestions included "A good ancestor," "Idealist," "Human," "Thinker," "Educated," "Brilliant," and the like. A few folks gamely stepped up to the challenge: "Regenerative designer," "Sustainer," and "Triple bottom liner" were among their suggestions.