Yonston, also a full-time SRI practitioner, works only with specifically SRI-focused mutual funds. And for clients with individual stocks and accounts, he can screen out investment instruments that contain certain sectors such as tobacco, alcohol, gambling, nuclear power and fossil fuels.
Alternatively, he can "screen in" investments that include sectors such as renewable energy, clean water, organic food, green building, or companies that employ best practices in terms of environmental, social and governance (ESG) issues.
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Performance has been very competitive compared to mainstream investments, Yonston said.
"There is a misconception," he said. "People think that by screening out certain companies, you're adversely limiting your universe.
"But this approach looks at quantitative aspects of investments, and also looks at ESG elements which fundamentally make for great, sustainable companies."