During a recent afternoon at The Phillips Collection, my friend Gail found a painting that inspired her to linger, sit on a nearby bench and say with a sigh, “I wish I had been friends with Duncan Phillips.” I agreed. The opulent rooms with Phillips’ collection of art in his old mansion at 21st and Q streets in Washington, D.C. are like no other in the area.

Duncan Phillips founded the museum in 1921 as a way to pay tribute to his father and brother who died in 1917 and 1918, respectively. His brother shared an avid interest in modern art and, with an allowance from their parents, they accumulated a stunning collection of works. After Duncan married, he and his wife Marjorie continued to collect pieces. In 1923, Phillips purchased Renoir’s “Luncheon of the Boating Party,” only one of the many masterpieces gracing the walls today in the permanent exhibit.

Around every corner is a treasure: Matisse, de Kooning, Rothko, O’Keeffe, van Gogh, and the small room filled with “The Migration Series” by Jacob Lawrence. And the spaces are enchanting with lovely fireplaces; gorgeous banisters; and a sumptuously grand, mahogany-paneled drawing room—the piece de resistance of the original house.

We strolled further, enjoying the equally pleasant, yet sleeker and more modern, Goh Annex, which, together with another building added in 2006, doubled the size of the original exhibit area.

This excerpt from their website explains the appeal of this engaging museum:

At the Phillips, works of art are hung in diverse groupings, which are meant to suggest visual “conversations” among the works in the viewer’s eye and mind.

“My arrangements are for the purpose of contrast and analogy,” Duncan Phillips once explained. “I bring together congenial spirits among the artists from different parts of the world and from different periods of time.”

As in any gathering, the conversational groups shift over time, with regular changes in the choice of works on display and their placement within the museum. Since galleries at the Phillips are not organized by categories or time periods, there is no specified order in which to see them. Instead, visitors wander freely, savoring the contrasts and correspondences among the “congenial spirits” in each room.

The spirit of Duncan Phillips’ legacy, and the dialogue between the paintings all play a part in the intimacy of this exquisite gallery—America’s first museum of modern art.