Private Independent Foundations
Family foundations are a subset of private foundations, and many private independent foundations have derived from the growth of a family foundation. The differentiation between a private independent and family foundation is the composition of its board, and, informally, the size of its corpus. In a family foundation, the majority of the trustees are family members; in a private independent foundation, trustees are those selected from the community for their expertise in or shared values with the foundation program areas. Private foundations (including family and private independent foundations), collectively, make nearly 90 percent of all grants made by foundations in the U.S. annually.
What are operating foundations, and how do they differ from the other types presented here?
Operating foundations do not make grants. Instead, they exist for one purpose, such as finding a cure for a disease, and commit their endowments to that effort and their own operations (including building the corpus through investment).

