Impact investing is growing, but bumps in the road remain as this slice of the investment universe expands around the globe. The fifth annual impact investor survey conducted by the Global Impact Investing Network (GIIN) and J.P. Morgan, which was released last month, captured data and perspectives from 146 impact investors including fund managers, foundations, banks and development finance institutions. Individual investors weren’t in the mix.

As defined by the GIIN, impact investments are directed at companies, organizations and funds with the goal of generating social and environmental impact in tandem with a financial return. They are made in both emerging and developed markets, and target a range of returns from below market to market rate, depending on the circumstances.

Impact investing is gaining momentum among institutional investors and other large entities, and is pushing its way into the consciousness of retail investors even if there still aren’t a lot of ways for individuals to get their skin in the game (see below).

The survey’s respondents—more than three-quarters are based in North America and Europe—said they committed an aggregate of $10.6 billion (in U.S. dollars) to impact investments last year and intend to raise that amount by 16% this year, to $12.2 billion. Of the 98 respondents who plan to commit more assets to impact investing in 2015 versus 2014, 55 said they intend to boost the amount by more than 50%.

In terms of assets under management per sector, housing was tops at 27%, followed by microfinance (16%), financial services ex-microfinance (11%) and energy (10%).

For 2015, the areas where impact investors plan to increase their allocations are Sub-Saharan Africa (29%), East and Southeast Africa (28%) and the Latin American/Caribbean region, including Mexico (27%).

Traditionally, impact investing isn’t a place to get rich because financial returns take a back seat to social and environmental returns. Private debt and private equity are the main investment vehicles of choice at 40% and 33% of AUM, respectively, followed by equity-like debt at 8%.

Financial returns can vary—some investments offer payouts in the higher-single-digit range while others basically break even. According to the survey, 55% of respondents said they aim for “competitive, market-rate returns,” while 27% said they seek “below-market-rate returns: closer to market rate” and 18% target “below-market-rate returns: closer to capital preservation.”

Meanwhile, large corporations are playing a more active role in the space, in part because internal and external stakeholders are pressuring them to weave social responsibility directly into their core business. That, in combination with tons of cash sitting on many corporate balance sheets, has led some companies to employ a corporate venture investing approach to making impact investments. Among them are Schneider Electric, a European multinational energy corporation; Pearson, a global educational company; and clothing maker Patagonia.

While this is all wonderful, many challenges remain in this sector. The top three, according to survey respondents, are a lack of appropriate capital across the risk/return spectrum; a shortage of high-quality investment opportunities with a track record; and difficulty in exiting positions. Others include the lack of a common way to talk about impact investing; not enough innovative deal/fund structures to accommodate investors’ or portfolio companies’ needs; insufficient research and data on products and performance; inadequate impact measurement standards; and a lack of investment professionals with relevant skill sets.

Those are a lot of challenges. That said, challenges are made to be overcome. And as demand for impact investing grows, count on more supply being created to accommodate demand.