Glenstone is a private contemporary art museum in Potomac, Maryland, founded in 2006 by American billionaire Mitchell Rales and his wife, Emily Wei Rales. The museum's exhibitions are drawn from a collection of about 1,300 works from post-World War II artists around the world. It is the largest private contemporary art museum in the United States, holding more than $4.6 billion in net assets, and is noted for its setting in a broad natural landscape.

Mitchell P. Rales is an American businessman and art collector best known for co-founding Danaher Corporation with his brother Steven Rales and the art museum Glenstone with his wife Emily Wei. Rales is also the chairman of ESAB, president of the National Gallery of Art, and a limited partner of the Washington Commanders of the National Football League (NFL). His net worth was estimated by Forbes in February 2024 to be $4.8 billion.