And both veteran foundations and new ones are seeing impact investing as a way to generate both a strong financial return and a social return by placing capital in socially oriented businesses and business-minded nonprofits.

Heron Foundation, and Jean Rogers, chief executive of the Sustainability Accounting Standards Board, wrote in the Stanford Social Innovation Review, foundations must deal with complex regulations governing their uses of assets, perceptions that social investments lead to lower returns, limited expertise in impact investing among the banks and other organizations that manage endowments, and the struggle to measure the performance of an investment with social returns.

Such concerns are important for foundations to weigh because before they undertake impact investing, they need to understand their appetite for risk and how willing they truly are to use their resources for maximum impact now and how much they are motivated by preserving assets for activities tomorrow.

And in some ways, foundations may find they have little choice: The century-old approach to foundation management, with its silos for investments and mission, may soon become obsolete because of the growing intensity of the problems facing the world.

Assessing sources of money for investments and scale of resources that will be committed to impact investments versus more conventional investments. Only half the foundations that the Foundation Center says make program-related investments (typically loans that charge below-market rates) have been offering loans for more than five years. A few foundations have made the leap to look at investments in a holistic way, but simply mixing philanthropy and investment has not magically led to better financial and social outcomes.

The appeal of impact investing for foundations is based on the idea that their capital can be a catalyst that bursts open a pinata of commercial and public money attracting incremental capital at scale to innovative and effective projects and enterprises.

Impact investing can’t resolve the cross-purposes that are inherent in the way today’s foundations operate, but it will become the must-have app if philanthropists expect to stay relevant.