Sonen Capital is a impact investment management firm headquartered in San Francisco.
They have published research reports that require one to register for their website, but are worth that small effort, including "Evolution of an Impact Portfolio", "2013 Annual Impact Report",
2014 Real Assets Primer (Sept 2014, 23 page pdf) illustrates investment opportunities in Sustainable Timberland, Sustainable Agriculture, Green Real Estate, Sustainable Ecosystems, & Green Infrastructure.
2013 Annual Impact Report (May 2014, 50 page pdf) describes Sonen's approach - and returns - from investing in public market companies and vehicles supporting Environmental, Social, & Governance (ESG) principles, and is a good overview of the ESG space.
Evolution of an Impact Portfolio (Oct 2013, 70 page pdf) chronicles the movement of the majority of a private foundation's assets into "impact investments" from 2006-2012. From the executive summary:
"We believe that the following performance discussion demonstrates that impact investments can compete with, and at times outperform, traditional asset allocation strategies, while simultaneously pursuing meaningful and measurable social and environmental impact. "
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