Government and donor funding alone will not be able to take on the environmental and climate change challenges we face today, so it is a promising development that “impact investing” is embracing environmental investments.

Environmental investing is not new. For more than 30 years, the David and Lucile Packard Foundation (where I work) has used loans and investments to help preserve important landscapes and ecosystems. In recent years, we have worked with a range of conservation partners and other like-minded mission-driven investors to create new financial vehicles for a wide variety of conservation impacts. These investment vehicles are scaling sustainable forestry and rangeland operations, supporting the development of carbon and water credits to fund environmental restoration, building environmental certification systems to influence markets, and growing environmentally sustainable fishing enterprises to help restore our oceans. And these are just some of the examples.

Yet environmental and conservation investing was omitted from the seminal 2010 Rockefeller Foundation and JP Morgan report that first publicized the term “impact investing” and helped build the field. The newly released Credit Suisse/WWF/ McKinsey report—which Fabian Huwyler, Juerg Kaeppeli, Katharina Serafimova, Eric Swanson, and John Tobin write about in their article—is an important step in helping impact investors to understand the full scope and opportunity of conservation investing. As a next step, the Packard and Gordon and Betty Moore foundations are working with The Nature Conservancy, JP Morgan Chase, and EKO in 2014 to further document the specific scope and types of future conservation investment opportunities. Stay tuned.

A note of caution: As environmental investing grows, we as investors will need to become more careful in how we identify and measure conservation impacts and be vigilant against “greenwashing” and the so-called “impact imposters.” As one step, our foundation worked in 2013 with a group of investment and nonprofit partners to build out IRIS conservation metrics. We hope that impact investors will use and refine them.

As we seek new sources to supplement traditional government funding for conservation, philanthropic investors like ourselves are increasingly “reaching across the aisle.” We are finding win-win-win partnerships, for example by co-investing with private equity and other financially-driven investors to restore the environment and combat climate change.

These multi-tiered projects and funds can be complicated and challenging, especially during this learning phase in the industry. But we must persevere. We must ensure that the environmental investments we make are structured to create deep and lasting conservation impacts that we can be proud of.

Read the rest of the responses.