I'd already picked Bill McKibben's Oil and Honey because it looks back at the recent history of environmental activism and forward to the more locally-and-globally sustainable patterns of living such activism was always supposed to enable.
And I'd picked Ed Wilson's The Creation because we can't reasonably hope to sustain life in a climate of polarized hostility over matters extraneous to our shared interest in survival. Environmental sustainability must transcend ideology and religion (and irreligion).
So yesterday I finally settled on Robin Attfield's freshly-revised and updated text. There's plenty here about sustainability and our responsibility to the future of life. There's defense of "biocentric consequentialism." There's an attempt to "foster the kind of campaigning" on behalf of the environment that moves us beyond the academic ivory tower and into the streets with McKibben and friends. There's a generous and helpful bibliography, including the web. There's "music for environmental ethicists." And there's the transatlantic perspective provided by Attfield's residence at Cardiff University.
But if I'm being entirely honest, one compelling reason for my selection of this text is the walkers on the cover. That's the picture of sustainability.