The Phillips Collection is showing three small exhibitions by three quite different painters: Judy Bass and Sherry Zvares Kasten, both of whom work here, and Ioannis Glykokokalos, who now lives in New York. Their three-part show, in sum, is greater than its parts.

Its unpretentious pictures -- carefully constructed, subtled in their colors and relatively small -- seem especially well suited for the nicely modest scale of that house-sized art museum. These are just the sort of paintings that the Phillips ought to show: those by relatively unknown, meritorious artists deserving of attention.

Kasten's works on paper, with their matching parallels and organizing grids, look much like abstractions, but become on second glance slightly out-of-focus scenes of urban excavations. Those stripes are reinforcing bars, those cylinders are steam pipes, those bands are boards or I-beams. The colors that prevail are the colors of raw lumber, rusting steel, earth. Kasten's works suggest the quiet of the cave. One imagines in their shadows dark, perhaps damp spaces that cannot be seen.

Two different kinds of light -- one harsh, the other subtle -- activate these pictures. The colors of her pipes, two-by-fours and girders are so closely tuned that the viewer feels as if he's squinting in the darkness. But that gloom is stabbed by slanting beams of sunlight so bright they hurt the eyes.

The one large triptych she is showing deals with a subject comparably unpretty: a factory-garage whose windowpanes are broken, whose concrete walls are gouged. Though the sun is shining, the facade is oddly blurred. The street signs can be clearly seen, but cannot be read. Kasten, who was born here in 1937, was trained at George Washington and American universities. What lends her pictures a sense of hush and mystery is that everything she paints is slightly indistinct.

Judy Bass is a fine colorist. She often lets us see one color through another; contrasts surfaces that glisten with others that are matte; and knows how to use a dozen shades of blue. Strange forms fly about in her half-abstract collages. A truncated pyramid hurtles through the air, a heavy wedge-shaped thing slides across what seems to be an oddly tilted floor. The bits of painted paper she fastens to her pictures are sometimes cut and sometimes torn; she drips paint and she scribbles. She clearly has learned much from postwar action painting, but does not fear perspective. Bass, 34, studied at George Washington and Maryland universities. The finest of her paintings here seem to open into places in which 3-D forms can play. Though these admirable paintings are full of speed and zoom, they are held in equilibrium by their modulated colors and a sense of air.

Ioannis Glykokokalos was born in 1937 on the Greek island of Lesbos, and studied for a while with an icon painter there. The small and carefully adjusted collages he is showing employ hacksaw blades and screws, lengths of hairy string and those bits of slotted cardboard that separate the bottles in cases of wine. Many of his pieces look like squashed found objected, picked up on the street, then lovingly considered, covered with thick paint and put in frames. Glykokokalos is attempting to pull something of the holy, or at least of the iconic, from the crummiest materials. But the objects remain a bit too precious -- in the wrong sense of that word. The three shows at the Phillips close Dec. 7.