National Gallery of Art - East Building

The National Gallery's East Building was constructed in the 1970s on much of the remaining land left over from the original congressional joint resolution utilizing funds from Mellon's children Paul Mellon and Ailsa Mellon Bruce. Designed by famed architect I.M. Pei, the contemporary structure was completed in 1978, and was opened on June 1 of that year by President Jimmy Carter.

Ieoh Ming Pei (貝聿銘) (b. April 26, 1917), commonly known by his initials I. M. Pei, is a Pritzker Prize-winning Chinese American architect, known as the last master of high modernist architecture. He works with the abstract form, using stone, concrete, glass, and steel. Pei is perhaps one of the most successful architects of the 20th century, with built work all over the world.

In 1989 Pei designed the famous Louvre Pyramid, in Paris France. Dan Brown incorporated Louvre Pyramid in his best-selling novel The Da Vinci Code.

It is ironic that I M Pei is of chinese origin yet chose as his motif the triangle, which transforms the building as a whole into the form that brings what chinese consider bad feng shui.

The East Building of the National Gallery of Art, employs the L'Enfant Angle in its architectural design.