The Hirshhorn Museum and Sculpture Garden, five years old this year, has been gradually, thoughtfully polishing its act. Its initial installation was a rather ragged chronological survey, but the Hirshhorn today offers a smoothly flowing sequence of small, instructive shows. They are drawn from its vast collection, which like some precious iceberg is mostly out of sight.

Some of these are little solo exhibitions, devoted, for example, to the art of Clyfford Still, Brancusi, Josef Albers or George Grosz. Others are group shows dealing with such themes as contemporary representational painting, color field, and collage. "Artists and Others: Some Portraits from the Collection," the newest exhibition there, makes not one point, but many. And it is a treat.

This exhibition does not survey styles and unlike, say, the collage show, it does not stress technique. Its message is more intimate. It suggests some of the many ways that artists look at other artists they admire, and it also lets us see how artists view themselves.

"Portrait of Myself and My Imaginary Wife," a little 1923 work by Arshile Gorky, is among the pictures shown. Beneath it on the wall is another head of Gorky, drawn by David Burliuk in 1941. The portrait on the wall beside them, this one by Raphael Soyer, shows David Burliuk's face. Though they might stand alone, these three pictures plaster start to sing sweetly to each other as they are displayed here. A plaster head of Soyer by Reuben Nakian accompanies these objects from across the room.

Thomas Eakins' portrait of William Merritt Chase pleasingly accompanies a little Chase self-portrait. The viewer's eye moves back and forth from one work to the other. Both pictures are more moving than they would be alone.

A number of the artists here pay homage to their heroes. A pair of Rodin bronzes present us with his visions of Balzac and Baudelaire.Emile-Antoine Bourdelle shows us Beethoven in a 1925 bronze. Using the same metal, Sir Jacob Epstein renders Somerset Maugham, while Reuben Nakian is represented by a loosely modeled likeness of Marcel Duchamp.

Other artists here show us pictures of their pals. A David Hockney line drawing done in 1973 portrays his friend Henry Geldzahler. Red Grooms shows us many of the people he hung out with in his "Loft on 26th Street" before that charming home was emptied and torn down.

Serious Kathe Kollwitz is represented by a bronze self-portrait. Raphael Soyer's portrait of Edwin Dickinson hangs beside a far more moving Dickinson, this one a self-portrait done in 1954.

Joseph H. Hirshhorn, the insatiable collector who brought these works together, is also in the show. His dark eyes, here conveying an expression of suspicion, peer from a Larry Rivers portrait of 1963.

Though his critics once accused him of indiscriminate collecting, few who see the Hirshhorn's current installations would make such a charge. Whether assembling these portraits, or buying the African Benin bronzes (which are now on view), or collecting Grosz or Eakins, he bought very well indeed. The late Duncan Phillips left a will requesting that his own collection be displayed in "units." The Hirshhorn's curators understand that works of art respond in telling, unexpected ways to the works displayed beside them. Duncan Phillips' good advice -- show works of art in units, not in isolation -- is now being followed, with admirable results, by those who run the Hirshhorn Museum on the Mall.