Many philanthropic investors are "dissatisfied with how much social change they’ve been able to create", Susan Wolf Ditkoff and Susan J. Colby, both partners at non-profit strategy consultant Bridgespan Group, say in the Harvard Business Review this month.

"Most of the 75,000 foundations in the United States (like their counterparts worldwide) know they must change, but they’re not sure how," Ditkoff and Colby say.

The authors also say that developing a philanthropic strategy requires the discipline to ask and rigorously answer three questions, which are:

• How do we define success?
• What will it take to make change happen?
• How can we improve our results over time?

The article looks at how major philanthropic leaders at the Bill & Melinda Gates Foundation, the David and Lucile Packard Foundation and the Annie E. Casey Foundation have wrestled with these questions.

For more information visit the Harvard Business Review website (subscription needed to view full article).