The presence of Pat Metheny on Jim Hall's 1998 By Arrangement fulfilled the younger guitarist's long-standing dream of recording with Hall. But these duets confirm how beautiful their performing together could become. Unlike many encounters between high-profile guitarists, these recordings, from both a New York studio and a Pittsburgh concert, show no sense of competition or interest in displays of empty virtuosity. Instead, the CD's true to the enduring spirit of Hall's music, emphasizing interaction and a subtle complexity. Hall plays the lightly amplified electric guitar that is his trademark, with a gorgeous liquid tone, while Metheny brings a bevy of instruments to the meeting, including a standard electric (no synth), several acoustics--including a fretless classical--and his 42-string model for some remarkably harplike effects. There's tremendous variety in the music and thought in the choices of tunes and approaches. "The Birds and the Bees," played in memory of its composer, the late guitarist Attila Zoller, has a haunting depth, while the frequently played "Summertime" achieves a new identity in Metheny's arrangement, with spare and vibrant lead contrasting with animated rhythm guitar. Both musicians are adept composers, and highlights include Metheny's "Ballad X" and Hall's increasingly propulsive "Cold Spring." Given that Hall participated in one of the first recorded examples of free improvisation, "Free Form" with the Chico Hamilton Quintet in 1955, and Metheny has recorded with the British avant-gardist Derek Bailey, it's fitting that the two guitarists test the limits of their empathy in five brief and intriguing collective improvisations that sometimes explore unusual textures and microtonal harmonies. Whatever the material, though, the earmarks of the set are a quiet energy and a sustained lyric invention that invite and reward repeated listenings. The recording quality is superb, capturing every nuance of this music that seems to live near the core of the jazz guitar ethos. --Stuart Broomer