Richard Wernick's piano concerto, which had its world premiere Thursday night at the Kennedy Center, is a tribute to friendship. Besides showing a profound stylistic and technical acquaintance with pianist Lambert Orkis, for whom it was written, the concerto contains Wernick's mementos of two deceased musical colleagues and a musicologist friend.

The result is music with a strong emotional impact and further evidence of why he has already won the two most prestigious awards reserved for American composers, the Pulitzer Prize and the Kennedy Center/Friedheim Award.

The first movement of the concerto is dedicated to Stephen Sell, the executive director of the Philadelphia Orchestra who died of lung cancer a few weeks before it was finished in July 1989. Its theme is "based on the bell signal they play at Philadelphia Orchestra concerts in the Academy of Music to tell the people it's time to take their seats," Wernick explains. "I composed that signal, and Steve was primarily responsible for my writing it, so I associate it with his memory."

The second movement begins and ends with ethereal, almost disembodied high-pitched sounds from metallic percussion and string harmonics. The sound seems curiously appropriate to the movement's odd title, "... the dream they smile and the kiss they whisper ..." The title, Wernick says, is from a poem, "Ball of the Sun," written by Bernard Jacobson, the musicologist and program annotator of the Philadelphia Orchestra, for which Wernick has served as a consultant since 1983. "I set that poem to music for Jan DeGaetani, a dear friend and perhaps the finest singer I have known," Wernick says. "She wanted to make another recording of American songs, and that would have been one of them. But she never sang that song; she died of leukemia. Fragments of the song provide the movement's thematic material."

The third and last movement, although not formally dedicated to Orkis and the National Symphony Orchestra, is tailored to them. "I wrote it for Lambert and the orchestra to enjoy themselves and show what they can do," Wernick says. As its title, "Rejouissance" ("Rejoicing"), indicates, the movement is an outburst of joy -- also of energy and vibrant orchestral color. "When you are writing for Lambert," he says, "you don't want to write colorless little miniatures."

This impression of the pianist's skills and personality is based on long acquaintance. "I have known Dick since about 1973," Orkis said a few days before the concerto's premiere. "I grew up in Philadelphia, studied at the Curtis Institute and then at Temple University, where I stayed on as a teacher and accompanist after getting my degree. When I began playing professionally, I really thought new music was for the birds, but I was converted by some of the things I played or heard: Lukas Foss's 'Time Cycle,' George Crumb's 'Black Angels,' Olivier Messiaen's 'Quartet for the End of Time.' I had to prepare the Messiaen in five days when the pianist originally scheduled for it became ill.

"I got to know Dick while working with the Penn Contemporary Players. He is the music director and conductor, and under his direction we all gave a full measure of effort. He was always very nice, but he seemed so stern and dedicated."

Orkis was first brought into the Washington music scene through his interest in contemporary music; Christopher Kendall, founder and director of the Twentieth Century Consort, looked long and hard for the right pianist before inviting Orkis to join the group, which is made up mostly of National Symphony members. From there, it was a natural next step for him to become the NSO's principal keyboard player, once Music Director Mstislav Rostropovich heard him playing with the consort.

He still commutes between Washington and Philadelphia, where he is professor of piano at Temple, but his center of gravity has shifted to Washington. In recent years, he has begun playing in the Smithsonian's historic instrument program. In his spare time, he travels extensively as a recital partner for Rostropovich, violinist Anne-Sophie Mutter and sopranos Lucy Shelton and Arleen Auger.

He kept up his contact with Wernick after moving to Washington, and eventually reached a key decision. "I already had some music written for me by George Crumb, the 'Little Suite for Christmas' that he gave me after he heard me play some of his music, and wanted some music by Dick Wernick too. So I told him, 'Dick, I would like to commission a piano sonata. I know it's expensive, but perhaps we could arrange a time payment plan.' The work that resulted, Wernick's "Sonata for Piano (Reflections of a Dark Light)," has been recorded by Orkis on the Bridge label with the Crumb suite and has won critical superlatives. As its title indicates, the sonata, like the concerto, has some deep emotional moments. "His son died while he was composing it," Orkis explains. "You can hear it in the music."

At first, it was not clear whether the concerto would be written for Wernick's orchestra in Philadelphia or Orkis's in Washington, but Orkis finally managed to work up the courage to ask Rostropovich to commission it. "It was in Tokyo," Orkis explains. "There was a reception after one of our recitals, everyone was feeling wonderful, the liquid refreshments were good and my inhibitions were lowered. So I said, 'Hey, Slava, you know this composer Richard Wernick?' 'Yes,' Slava said, 'I heard you play his Piano Sonata -- very difficult.' So I suggested that he commission a concerto and he agreed on the spot. Just to be sure, I asked him again later, when we weren't at a party, and he still thought it was a good idea. So he went to the Hechinger Foundation, got a commission, and now there is a new piece of music."