Can investors make socially responsible investments and still expect to make as much money as they otherwise would? And should not-for-profit organisations expect to pay market rates when borrowing?
These questions lay behind the announcement last week by social lender Bridges Ventures that it was launching a £26m property fund that would invest in property with an environmental and social benefit, but would aim to offer the same returns as a normal commercial fund.
Michele Giddens, executive director at Bridges, says the answer to both questions is usually "yes".
"A lot of people feel you can receive a social return only if you accept a lower financial return," she says. "We have launched funds that sacrifice financial return for social return, but we want to show with this one that it doesn't have to be the case. This is intended to show that you can make money while doing good."
The expectation that offering a social return means cheaper capital could limit the size of the social finance market, some experts believe.
"Many people seeking social investment are coming from a grant-maintained background and still have that ethos," says Geoff Burnand, co-founder of Investing for Good, which helps social investors find projects for their money. "They expect to get cheap rates because they are offering social good.
"But that way of thinking needs to change, because it limits the amount of money available.
"There are people who will invest money at a sub-market rate of return, but there are many more people who will lend at the market rate."
Penny Shepherd, chief executive of sustainable finance organisation Uksif, says that social borrowers should follow the model of fair-trade coffee.
"Fair-trade coffee is just as good as regular coffee," she says. "But it has an ethical angle. A few people might drink it even if it cost more. But most people would buy it only if it cost the same as other products.
"The same is true of social investment. Many people will do it, but only if it doesn't cost them anything."