"Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs."
That definition, from the report  of the Brundtland Commission, is familiar to all of us who work on campus sustainability. Since our efforts are most often focused on operations, not development (except, perhaps, in the specific way that term is used by colleges and universities), we often rephrase it in terms of "sustainability" rather than "sustainable development." But the rest of the sentence remains unchanged. And it's the rest of the sentence about which I had a realization this morning.
The Brundtland Report came out in 1987. 1987 was 24 years ago. Most of the students to whom I speak about sustainability (certainly, most of the undergraduates) aren't yet 24 years old.
Which is to say, for most of my students, "future generations" doesn't start with their children. It starts with them. Kind of puts an edge on things, doesn't it?