Sustainable investing is booming. The industry has spawned its own lingo—ESG, SASB, SRI, GRI—dedicated to describing this seemingly moral turn in the finance industry, where money is invested in ways that make the world a better place. After all, it feels good to generate a return while promoting the SDGs (that’s the UN’s sustainable development goals, if you’re wondering).

According to the latest report by the US Forum for Sustainable and Responsible Investment (US SIF), investors now consider environmental, social, and governance (ESG) factors for $12 trillion of professionally managed assets. That’s a 38% increase from 2016. It’s also out of a total universe of $46.6 trillion of professionally managed assets in the US. That means that almost a quarter of assets could now be considered “sustainably” or “responsibly” invested.

These already big numbers are expected to get even bigger. A recent HSBC survey of more than 1,700 investors and issuers around the world showed that 60% of investors and just under half of issuers have an ESG strategy. The proportion for both rises to more than 80% in Europe. Asset managers around the world speak eagerly about a wave of millennial investors ready to pour their money into sustainable investments. And this isn’t just virtue signaling: More people now accept the conclusions of academic studies that say socially responsible investing doesn’t sacrifice financial returns.

If this all sounds too good to be true, that’s because it might be.

The world of sustainable and socially responsible finance lacks structure and standards. Without these, there’s little to protect against “greenwashing”—firms and fund managers saying they are adhering to ESG principles without following through on them. There are no firm definitions of what counts as ESG investing, which allows many to make it so expansive that it becomes nearly meaningless. (The EU is trying to combat this.) The industry needs a gatekeeper.

Integration or impact?

The confusion begins with the terminology. Swiss bank UBS surveyed more than 5,000 of its wealthiest clients and found little understanding of the differences between the three main approaches to sustainable and socially responsible investing: exclusion, integration, and impact investing. 1 Plus, less than 40% of respondents said they had sustainable investments in their portfolio.

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