There's now more data to support the idea that doing well and doing good are not mutually exclusive.
A new study from investment consultant Cambridge Associates and the Global Impact Investing Network shows that private equity and venture capital funds with so-called impact missions produce roughly the same returns as funds just trying to make as much money as possible.
Some 51 impact funds, which bet on businesses that help people or causes, launched between 1998 and 2010 returned an average of 6.9 percent per year to investors through June 2014 versus 8.1 percent for 705 nonimpact funds.
However, a more representative sample are funds raised from 1998 and 2004 as they have mostly cashed out of their multiyear investments. The seven impact funds launched from 1998 to 2001 gained an average of 15.6 percent versus 5.5 percent; nine impact funds launched from 2002 to 2004 gained 7.6 percent versus 7.7 percent.
"There's a view among some investors that impact investing necessarily entails a sacrifice in financial return," Jessica Matthews, head of Cambridge's mission-related investing group, said in a statement. "However, this data helps to show that is more perception than reality."
Certain types of impact funds had even stronger returns, according to the study.
Smaller funds—those that raised less than $100 million—returned an average of 9.5 percent to investors, versus 4.5 percent for nonimpact vehicles. Such small funds focusing on the U.S. returned 13.1 percent versus 3.6 percent for comparative nonimpact U.S. funds.
Emerging market-focused impact funds also did well: a return of 9.1 percent versus a developed markets benchmark of 4.8 percent. Those focused on Africa produced even stronger results, returning 9.7 percent, according to the data.
To be sure, the sample set of 51 impact funds is relatively small, and 35 of 51 were launched from 2005 to 2010, meaning their full returns are not yet available.
"Given the limited size of the sample and the overall youth of the funds ... it is difficult to draw definitive conclusions on the performance of impact investing funds," the study states as a caveat to its preliminary findings.