Interesting partnership announced today—private equity firm KKR joining with Environmental Defense Fund to come up with tools for measuring the environmental footprint of KKR’s portfolio companies. It’s the topic of today’s Sustainability column.

Here’s how it begins:

Private equity firms are renowned — and occasionally denounced — for squeezing costs out of companies they buy. Their investors say buyout funds help the economy become more efficient, and build shareholder value. Their critics allege that they do so by exploiting workers, avoiding taxes and polluting the planet.

We won’t try to settle that argument here, but it provides a useful context for Thursday’s announcement of a partnership between Kohlberg Kravis Roberts, one of the world’s leading buyout firms, and the Environmental Defense Fund, a nonprofit environmental group. Their “green portfolio” partnership — the first between a big private equity fund and an environmental group — is intended to measure and improve the environmental performance of KKR’s U.S. companies

This news is, all at once, significant, surprising and predictable.

You can read the rest here.