The Gardner is the namesake of the museum's founder, art collector, and curator, Isabella Stewart Gardner. The original building (formerly named "Fenway Court") is infused with a blend of architectural styles, inspired by her European travels. She played an active, hands-on role in the design and construction process, animating the space with her eye for detail and preference for eccentricity and opulence. Imprints of her design sensibilities are visible in the unique, pink stucco courtyard walls and the textured Gothic Room beams. She curated her own collection by arranging and re-arranging the art in her museum. Isabella's motto is displayed on a stone carving above the original entrance: "C'est mon plaisir" ("It is my pleasure").
The dynamic collection of European, Asian, and American art, features over 17,000 paintings, sculptures, furniture, textiles and tapestries, silver and ceramics, books, and archival objects. On March 18, 1990, 13 works of art were stolen from the museum in a theft that remains unsolved. "This Is a Robbery: The World's Biggest Art Heist" docuseries on Netflix explores the ongoing search for $500 million worth of artwork.A glass and copper-clad modern addition complements the historic architecture with over 70,000 additional square feet, making room for expanded programming. The new wing provides a bustling complement to the serenity of the historic palace. The form of the expansion features four volumes that seem to levitate above the transparent first floor. Characteristic of Piano's work, glass facades and skylights abound, creating a light and functional space that contrasts with the heaviness of the original museum building. The design privileged sustainability features, such as a geothermal well system, daylight harvesting, water efficient landscaping techniques, and the use of local and regional materials.