Just as the conscious consumer will choose the fair trade bananas at the supermarket, they also need to have a concern for what the money they have sitting in the bank is doing in their name.
That's quite significant, he says.
For example, if someone were to divest from shares in a fossil fuel company as a result of concerns about climate change, unless there is a massive sea change in investor behaviour, someone else is going to buy those shares. The overall impact might be negligible.
But if a bank decides it is no longer going to lend to oil explorers because they have a policy on it, that can have a very real impact on whether an oil project goes ahead, he says.
``They are finding this in Australia in particular. There are big coal-mining projects that are stalled at the moment because the coalminers can't find banks that are willing to lend them the capital to make it happen,'' Dr Russell says.
