Even though foundation grants make up a small percentage of annual health spending in the U.S., they can have a huge impact on health. By supplementing the private and government funding of healthcare, health research, and public health, foundation grants provide an important opportunity to implement new and innovative solutions to today’s health challenges. The impact of these grants, however, would be much less if organizations lost current funding from other sources when they received a new grant from a foundation. For this reason, MHCF funds should not be used to supplant other sources of funding. Moreover, according to Montana law, MHCF funds may not be used to supplant government funds. This brief explains MHCF’s requirements to prevent supplanting of other sources of funds.