Margrit Biever Mondavi is Vice President of Cultural Affairs at Robert Mondavi Winery which she joined in 1967. Under her direction, Robert Mondavi Winery developed original cultural and culinary arts programs. In 1980, she married Robert Mondavi and worked with him in many of his philanthropic activities including the founding of COPIA: The American Center for Wine, Food and the Arts. Margrit played a key role in securing the downtown Napa location for the center, which opened in November 2001.

When Margrit started working at Robert Mondavi Winery, there were very few visitors frequenting Napa Valley. One of the first things Margrit did was establish a fine arts program at the winery that brought many different kinds of artists to the winery including Richard Diebenkorn, Wayne Thiebaud and Nathan Oliveira.

Margrit founded the winery’s Summer Music Festival in 1969 as a benefit for the Napa Valley Symphony. This concert series has hosted many jazz, R&B and pop artists including Ella Fitzgerald, Harry Belafonte and Tony Bennett. The Mondavi Summer Jazz Festival opens with the New Orleans Jazz Band Preservation Hall.

In 1984, the Festival of Winter Classical Concert Series was created, with the proceeds benefiting local musical organizations like the Napa Valley Opera. Together with Veronica di Rosa, Margrit and a small group of other Napa Valley art lovers formed a board of directors to rebuild the original 19th-century opera house in the city of Napa. She organized fundraising events, including art auctions, to keep the opera house alive. In 1998, the opera raised significant funds for the restoration as part of a challenge grant from Margrit and Robert Mondavi; the renovated opera house opened in October 2002.